diff --git a/TestVectors/all.txt b/TestVectors/all.txt
index a9749c6b..62d44795 100644
--- a/TestVectors/all.txt
+++ b/TestVectors/all.txt
@@ -10,4 +10,5 @@ Test: rsa_oaep.txt
 Test: rsa_pkcs1_1_5.txt
 Test: rsa_pss.txt
 Test: rw.txt
+Test: seal.txt
 Test: sha.txt
diff --git a/TestVectors/seal.txt b/TestVectors/seal.txt
new file mode 100644
index 00000000..a98812ba
--- /dev/null
+++ b/TestVectors/seal.txt
@@ -0,0 +1,138 @@
+AlgorithmType: SymmetricCipher
+Name: SEAL-3.0-BE
+Source: generated by Crypto++ 5.2
+Comment: verified against partial ciphertext from 1997 SEAL paper by Rogaway and Coppersmith
+Key: 67452301efcdab8998badcfe10325476c3d2e1f0
+IV: 013577af
+Plaintext: r1024 00000000
+Ciphertext: \
+37a005959b84c49ca4be1e050673530f5fb097fdf6a13fbd6c2cdecd81fdee7c\
+2abdc3e764209aff00a12283ef675085c1634b53289059e6a7ab5ed9480c01eb\
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+585a2905f0496ba58eb3d740efa54b664d1a6134fed9fede636504aa691e08e4
+Test: Encrypt
+Test: Decrypt
diff --git a/arc4.cpp b/arc4.cpp
index 7d8d05a5..407c75c6 100644
--- a/arc4.cpp
+++ b/arc4.cpp
@@ -21,7 +21,7 @@ ARC4_Base::~ARC4_Base()
 	m_x = m_y = 0;
 }
 
-void ARC4_Base::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int keyLen)
+void ARC4_Base::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int keyLen, const byte *iv)
 {
 	AssertValidKeyLength(keyLen);
 
diff --git a/arc4.h b/arc4.h
index 51de9f12..cfb7de69 100644
--- a/arc4.h
+++ b/arc4.h
@@ -27,7 +27,7 @@ public:
 	typedef SymmetricCipherFinalTemplate<ARC4_Base> Decryption;
 
 protected:
-	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length);
+	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv);
 	virtual unsigned int GetDefaultDiscardBytes() const {return 0;}
 
     FixedSizeSecBlock<byte, 256> m_state;
diff --git a/cryptlib.cpp b/cryptlib.cpp
index e3fe2d5f..07dd87c0 100644
--- a/cryptlib.cpp
+++ b/cryptlib.cpp
@@ -57,6 +57,28 @@ void SimpleKeyingInterface::ThrowIfInvalidKeyLength(const Algorithm &algorithm,
 		throw InvalidKeyLength(algorithm.AlgorithmName(), length);
 }
 
+void SimpleKeyingInterface::ThrowIfResynchronizable()
+{
+	if (IsResynchronizable())
+		throw InvalidArgument("SimpleKeyingInterface: this object requires an IV");
+}
+
+void SimpleKeyingInterface::ThrowIfInvalidIV(const byte *iv)
+{
+	if (!iv && !(IVRequirement() == INTERNALLY_GENERATED_IV || IVRequirement() == STRUCTURED_IV || !IsResynchronizable()))
+		throw InvalidArgument("SimpleKeyingInterface: this object cannot use a null IV");
+}
+
+const byte * SimpleKeyingInterface::GetIVAndThrowIfInvalid(const NameValuePairs &params)
+{
+	const byte *iv;
+	if (params.GetValue(Name::IV(), iv))
+		ThrowIfInvalidIV(iv);
+	else
+		ThrowIfResynchronizable();
+	return iv;
+}
+
 void BlockTransformation::ProcessAndXorMultipleBlocks(const byte *inBlocks, const byte *xorBlocks, byte *outBlocks, unsigned int numberOfBlocks) const
 {
 	unsigned int blockSize = BlockSize();
diff --git a/cryptlib.h b/cryptlib.h
index 27783971..31e32e8f 100644
--- a/cryptlib.h
+++ b/cryptlib.h
@@ -381,6 +381,9 @@ public:
 
 protected:
 	void ThrowIfInvalidKeyLength(const Algorithm &algorithm, unsigned int length);
+	void ThrowIfResynchronizable();			// to be called when no IV is passed
+	void ThrowIfInvalidIV(const byte *iv);	// check for NULL IV if it can't be used
+	const byte * GetIVAndThrowIfInvalid(const NameValuePairs &params);
 
 	inline void AssertValidKeyLength(unsigned int length) const
 	{
diff --git a/datatest.cpp b/datatest.cpp
index 50b26fe2..13077602 100644
--- a/datatest.cpp
+++ b/datatest.cpp
@@ -197,7 +197,7 @@ privateKeyTests:
 	}
 }
 
-void TestEncryptionScheme(TestData &v)
+void TestAsymmetricCipher(TestData &v)
 {
 	std::string name = GetRequiredDatum(v, "Name");
 	std::string test = GetRequiredDatum(v, "Test");
@@ -237,6 +237,41 @@ void TestEncryptionScheme(TestData &v)
 	}
 }
 
+void TestSymmetricCipher(TestData &v)
+{
+	std::string name = GetRequiredDatum(v, "Name");
+	std::string test = GetRequiredDatum(v, "Test");
+
+	std::string key = GetDecodedDatum(v, "Key");
+	std::string iv = GetDecodedDatum(v, "IV");
+	std::string ciphertext = GetDecodedDatum(v, "Ciphertext");
+	std::string plaintext = GetDecodedDatum(v, "Plaintext");
+
+	if (test == "Encrypt")
+	{
+		std::auto_ptr<SymmetricCipher> encryptor(ObjectFactoryRegistry<SymmetricCipher, ENCRYPTION>::Registry().CreateObject(name.c_str()));
+		encryptor->SetKeyWithIV((const byte *)key.data(), key.size(), (const byte *)iv.data());
+		std::string encrypted;
+		StringSource ss(plaintext, true, new StreamTransformationFilter(*encryptor, new StringSink(encrypted), StreamTransformationFilter::NO_PADDING));
+		if (encrypted != ciphertext)
+			SignalTestFailure();
+	}
+	else if (test == "Decrypt")
+	{
+		std::auto_ptr<SymmetricCipher> decryptor(ObjectFactoryRegistry<SymmetricCipher, DECRYPTION>::Registry().CreateObject(name.c_str()));
+		decryptor->SetKeyWithIV((const byte *)key.data(), key.size(), (const byte *)iv.data());
+		std::string decrypted;
+		StringSource ss(ciphertext, true, new StreamTransformationFilter(*decryptor, new StringSink(decrypted), StreamTransformationFilter::NO_PADDING));
+		if (decrypted != plaintext)
+			SignalTestFailure();
+	}
+	else
+	{
+		SignalTestError();
+		assert(false);
+	}
+}
+
 void TestDigestOrMAC(TestData &v, bool testDigest)
 {
 	std::string name = GetRequiredDatum(v, "Name");
@@ -391,8 +426,10 @@ void TestDataFile(const std::string &filename, unsigned int &totalTests, unsigne
 			{
 				if (algType == "Signature")
 					TestSignatureScheme(v);
+				else if (algType == "SymmetricCipher")
+					TestSymmetricCipher(v);
 				else if (algType == "AsymmetricCipher")
-					TestEncryptionScheme(v);
+					TestAsymmetricCipher(v);
 				else if (algType == "MessageDigest")
 					TestDigestOrMAC(v, true);
 				else if (algType == "MAC")
diff --git a/factory.h b/factory.h
index 893a731f..1dd0bdc3 100644
--- a/factory.h
+++ b/factory.h
@@ -24,7 +24,7 @@ public:
 	
 };
 
-template <class AbstractClass>
+template <class AbstractClass, int instance=0>
 class ObjectFactoryRegistry
 {
 public:
@@ -55,38 +55,46 @@ public:
 	}
 
 	// VC60 workaround: use "..." to prevent this function from being inlined
-	static ObjectFactoryRegistry<AbstractClass> & Registry(...);
+	static ObjectFactoryRegistry<AbstractClass, instance> & Registry(...);
 
 private:
 	typedef std::map<std::string, ObjectFactory<AbstractClass> *> Map;
 	Map m_map;
 };
 
-template <class AbstractClass>
-ObjectFactoryRegistry<AbstractClass> & ObjectFactoryRegistry<AbstractClass>::Registry(...)
+template <class AbstractClass, int instance>
+ObjectFactoryRegistry<AbstractClass, instance> & ObjectFactoryRegistry<AbstractClass, instance>::Registry(...)
 {
-	static ObjectFactoryRegistry<AbstractClass> s_registry;
+	static ObjectFactoryRegistry<AbstractClass, instance> s_registry;
 	return s_registry;
 }
 
-template <class AbstractClass, class ConcreteClass>
-void RegisterDefaultFactoryFor(const char *name, AbstractClass *Dummy1=NULL, ConcreteClass *Dummy2=NULL)
+template <class AbstractClass, class ConcreteClass, int instance = 0>
+struct RegisterDefaultFactoryFor {
+RegisterDefaultFactoryFor(const char *name)
 {
-	ObjectFactoryRegistry<AbstractClass>::Registry().RegisterFactory(name, new DefaultObjectFactory<AbstractClass, ConcreteClass>);
-}
+	ObjectFactoryRegistry<AbstractClass, instance>::Registry().RegisterFactory(name, new DefaultObjectFactory<AbstractClass, ConcreteClass>);
+}};
 
 template <class SchemeClass>
-void RegisterPublicKeyCryptoSystemDefaultFactories(const char *name, SchemeClass *dummy=NULL)
+void RegisterAsymmetricCipherDefaultFactories(const char *name, SchemeClass *dummy=NULL)
 {
-	RegisterDefaultFactoryFor<PK_Encryptor, CPP_TYPENAME SchemeClass::Encryptor>(name);
-	RegisterDefaultFactoryFor<PK_Decryptor, CPP_TYPENAME SchemeClass::Decryptor>(name);
+	RegisterDefaultFactoryFor<PK_Encryptor, CPP_TYPENAME SchemeClass::Encryptor>((const char *)name);
+	RegisterDefaultFactoryFor<PK_Decryptor, CPP_TYPENAME SchemeClass::Decryptor>((const char *)name);
 }
 
 template <class SchemeClass>
 void RegisterSignatureSchemeDefaultFactories(const char *name, SchemeClass *dummy=NULL)
 {
-	RegisterDefaultFactoryFor<PK_Signer, CPP_TYPENAME SchemeClass::Signer>(name);
-	RegisterDefaultFactoryFor<PK_Verifier, CPP_TYPENAME SchemeClass::Verifier>(name);
+	RegisterDefaultFactoryFor<PK_Signer, CPP_TYPENAME SchemeClass::Signer>((const char *)name);
+	RegisterDefaultFactoryFor<PK_Verifier, CPP_TYPENAME SchemeClass::Verifier>((const char *)name);
+}
+
+template <class SchemeClass>
+void RegisterSymmetricCipherDefaultFactories(const char *name, SchemeClass *dummy=NULL)
+{
+	RegisterDefaultFactoryFor<SymmetricCipher, CPP_TYPENAME SchemeClass::Encryption, ENCRYPTION>((const char *)name);
+	RegisterDefaultFactoryFor<SymmetricCipher, CPP_TYPENAME SchemeClass::Decryption, DECRYPTION>((const char *)name);
 }
 
 NAMESPACE_END
diff --git a/modes.cpp b/modes.cpp
index 70c23234..09c370ee 100644
--- a/modes.cpp
+++ b/modes.cpp
@@ -32,7 +32,7 @@ template class AdditiveCipherTemplate<AbstractPolicyHolder<AdditiveCipherAbstrac
 
 void CipherModeBase::SetKey(const byte *key, unsigned int length, const NameValuePairs &params)
 {
-	UncheckedSetKey(params, key, length);	// the underlying cipher will check the key length
+	UncheckedSetKey(params, key, length, GetIVAndThrowIfInvalid(params));	// the underlying cipher will check the key length
 }
 
 void CipherModeBase::GetNextIV(byte *IV)
@@ -44,22 +44,6 @@ void CipherModeBase::GetNextIV(byte *IV)
 	memcpy(IV, m_register, BlockSize());
 }
 
-void CipherModeBase::SetIV(const byte *iv)
-{
-	if (iv)
-		Resynchronize(iv);
-	else if (IsResynchronizable())
-	{
-		if (!CanUseStructuredIVs())
-			throw InvalidArgument("CipherModeBase: this cipher mode cannot use a null IV");
-
-		// use all zeros as default IV
-		SecByteBlock iv(BlockSize());
-		memset(iv, 0, iv.size());
-		Resynchronize(iv);
-	}
-}
-
 void CTR_ModePolicy::SeekToIteration(dword iterationCount)
 {
 	int carry=0;
@@ -126,17 +110,17 @@ void CTR_ModePolicy::OperateKeystream(KeystreamOperation operation, byte *output
 void CTR_ModePolicy::CipherResynchronize(byte *keystreamBuffer, const byte *iv)
 {
 	unsigned int s = BlockSize();
-	memcpy(m_register, iv, s);
+	CopyOrZero(m_register, iv, s);
 	m_counterArray.New(s * m_cipher->OptimalNumberOfParallelBlocks());
-	memcpy(m_counterArray, iv, s);
+	CopyOrZero(m_counterArray, iv, s);
 }
 
-void BlockOrientedCipherModeBase::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length)
+void BlockOrientedCipherModeBase::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv)
 {
 	m_cipher->SetKey(key, length, params);
 	ResizeBuffers();
-	const byte *iv = params.GetValueWithDefault(Name::IV(), (const byte *)NULL);
-	SetIV(iv);
+	if (IsResynchronizable())
+		Resynchronize(iv);
 }
 
 void BlockOrientedCipherModeBase::ProcessData(byte *outString, const byte *inString, unsigned int length)
diff --git a/modes.h b/modes.h
index 46e8dd26..9a94f379 100644
--- a/modes.h
+++ b/modes.h
@@ -47,7 +47,6 @@ public:
 
 protected:
 	inline unsigned int BlockSize() const {assert(m_register.size() > 0); return m_register.size();}
-	void SetIV(const byte *iv);
 	virtual void SetFeedbackSize(unsigned int feedbackSize)
 	{
 		if (!(feedbackSize == 0 || feedbackSize == BlockSize()))
@@ -57,7 +56,7 @@ protected:
 	{
 		m_register.New(m_cipher->BlockSize());
 	}
-	virtual void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length) =0;
+	virtual void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv) =0;
 
 	BlockCipher *m_cipher;
 	SecByteBlock m_register;
@@ -73,8 +72,6 @@ class ModePolicyCommonTemplate : public CipherModeBase, public POLICY_INTERFACE
 		ResizeBuffers();
 		int feedbackSize = params.GetIntValueWithDefault(Name::FeedbackSize(), 0);
 		SetFeedbackSize(feedbackSize);
-		const byte *iv = params.GetValueWithDefault(Name::IV(), (const byte *)NULL);
-		SetIV(iv);
 	}
 };
 
@@ -113,6 +110,14 @@ protected:
 	unsigned int m_feedbackSize;
 };
 
+inline void CopyOrZero(void *dest, const void *src, size_t s)
+{
+	if (src)
+		memcpy(dest, src, s);
+	else
+		memset(dest, 0, s);
+}
+
 class OFB_ModePolicy : public ModePolicyCommonTemplate<AdditiveCipherAbstractPolicy>
 {
 	unsigned int GetBytesPerIteration() const {return BlockSize();}
@@ -124,7 +129,7 @@ class OFB_ModePolicy : public ModePolicyCommonTemplate<AdditiveCipherAbstractPol
 	}
 	void CipherResynchronize(byte *keystreamBuffer, const byte *iv)
 	{
-		memcpy(keystreamBuffer, iv, BlockSize());
+		CopyOrZero(keystreamBuffer, iv, BlockSize());
 	}
 	bool IsRandomAccess() const {return false;}
 	IV_Requirement IVRequirement() const {return STRUCTURED_IV;}
@@ -151,7 +156,7 @@ class CTR_ModePolicy : public ModePolicyCommonTemplate<AdditiveCipherAbstractPol
 class BlockOrientedCipherModeBase : public CipherModeBase
 {
 public:
-	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length);
+	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv);
 	unsigned int MandatoryBlockSize() const {return BlockSize();}
 	bool IsRandomAccess() const {return false;}
 	bool IsSelfInverting() const {return false;}
@@ -202,9 +207,9 @@ public:
 	void ProcessLastBlock(byte *outString, const byte *inString, unsigned int length);
 
 protected:
-	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length)
+	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv)
 	{
-		CBC_Encryption::UncheckedSetKey(params, key, length);
+		CBC_Encryption::UncheckedSetKey(params, key, length, iv);
 		m_stolenIV = params.GetValueWithDefault(Name::StolenIV(), (byte *)NULL);
 	}
 
@@ -250,7 +255,7 @@ public:
 	CipherModeFinalTemplate_CipherHolder(const byte *key, unsigned int length, const byte *iv, int feedbackSize = 0)
 	{
 		m_cipher = &m_object;
-		SetKey(key, length, MakeParameters("IV", iv)("FeedbackSize", feedbackSize));
+		SetKey(key, length, MakeParameters(Name::IV(), iv)(Name::FeedbackSize(), feedbackSize));
 	}
 };
 
@@ -259,12 +264,21 @@ template <class BASE>
 class CipherModeFinalTemplate_ExternalCipher : public BASE
 {
 public:
-	CipherModeFinalTemplate_ExternalCipher(BlockCipher &cipher, const byte *iv = NULL, int feedbackSize = 0)
+	CipherModeFinalTemplate_ExternalCipher(BlockCipher &cipher)
 	{
+		ThrowIfResynchronizable();
+		m_cipher = &cipher;
+		ResizeBuffers();
+	}
+
+	CipherModeFinalTemplate_ExternalCipher(BlockCipher &cipher, const byte *iv, int feedbackSize = 0)
+	{
+		ThrowIfInvalidIV(iv);
 		m_cipher = &cipher;
 		ResizeBuffers();
 		SetFeedbackSize(feedbackSize);
-		SetIV(iv);
+		if (IsResynchronizable())
+			Resynchronize(iv);
 	}
 };
 
diff --git a/panama.h b/panama.h
index a24113d0..30b6390c 100644
--- a/panama.h
+++ b/panama.h
@@ -82,7 +82,7 @@ struct PanamaCipherInfo : public VariableKeyLength<32, 32, 64, 32, SimpleKeyingI
 
 //! .
 template <class B>
-class PanamaCipherPolicy : public AdditiveCipherConcretePolicy<word32, 32>, 
+class PanamaCipherPolicy : public AdditiveCipherConcretePolicy<word32, 8>, 
 							public PanamaCipherInfo<B>,
 							protected Panama<B>
 {
diff --git a/regtest.cpp b/regtest.cpp
index b01351fc..d691d46a 100644
--- a/regtest.cpp
+++ b/regtest.cpp
@@ -9,6 +9,7 @@
 #include "rsa.h"
 #include "ripemd.h"
 #include "dsa.h"
+#include "seal.h"
 
 USING_NAMESPACE(CryptoPP)
 
@@ -22,8 +23,8 @@ void RegisterFactories()
 	RegisterDefaultFactoryFor<MessageAuthenticationCode, HMAC<MD5> >("HMAC(MD5)");
 	RegisterDefaultFactoryFor<MessageAuthenticationCode, HMAC<SHA1> >("HMAC(SHA-1)");
 	RegisterDefaultFactoryFor<MessageAuthenticationCode, HMAC<RIPEMD160> >("HMAC(RIPEMD-160)");
-	RegisterPublicKeyCryptoSystemDefaultFactories<RSAES<OAEP<SHA1> > >("RSA/OAEP-MGF1(SHA-1)");
-	RegisterPublicKeyCryptoSystemDefaultFactories<DLIES<> >("DLIES(NoCofactorMultiplication, KDF2(SHA-1), XOR, HMAC(SHA-1), DHAES)");
+	RegisterAsymmetricCipherDefaultFactories<RSAES<OAEP<SHA1> > >("RSA/OAEP-MGF1(SHA-1)");
+	RegisterAsymmetricCipherDefaultFactories<DLIES<> >("DLIES(NoCofactorMultiplication, KDF2(SHA-1), XOR, HMAC(SHA-1), DHAES)");
 	RegisterSignatureSchemeDefaultFactories<DSA>("DSA(1363)");
 	RegisterSignatureSchemeDefaultFactories<NR<SHA1> >("NR(1363)/EMSA1(SHA-1)");
 	RegisterSignatureSchemeDefaultFactories<GDSA<SHA1> >("DSA-1363/EMSA1(SHA-1)");
@@ -32,4 +33,5 @@ void RegisterFactories()
 	RegisterSignatureSchemeDefaultFactories<ESIGN<SHA1> >("ESIGN/EMSA5-MGF1(SHA-1)");
 	RegisterSignatureSchemeDefaultFactories<RWSS<P1363_EMSA2, SHA1> >("RW/EMSA2(SHA-1)");
 	RegisterSignatureSchemeDefaultFactories<RSASS<PSS, SHA1> >("RSA/PSS-MGF1(SHA-1)");
+	RegisterSymmetricCipherDefaultFactories<SEAL<> >("SEAL-3.0-BE");
 }
diff --git a/seal.cpp b/seal.cpp
index 97362233..a478f9a5 100644
--- a/seal.cpp
+++ b/seal.cpp
@@ -69,7 +69,7 @@ void SEAL_Policy<B>::CipherSetKey(const NameValuePairs &params, const byte *key,
 template <class B>
 void SEAL_Policy<B>::CipherResynchronize(byte *keystreamBuffer, const byte *IV)
 {
-	m_outsideCounter = UnalignedGetWord<word32>(BIG_ENDIAN_ORDER, IV);
+	m_outsideCounter = IV ? UnalignedGetWord<word32>(BIG_ENDIAN_ORDER, IV) : 0;
 	m_startCount = m_outsideCounter;
 	m_insideCounter = 0;
 }
diff --git a/seal.h b/seal.h
index 0e9f025d..4fc7e887 100644
--- a/seal.h
+++ b/seal.h
@@ -12,7 +12,7 @@ struct SEAL_Info : public FixedKeyLength<20, SimpleKeyingInterface::INTERNALLY_G
 };
 
 template <class B = BigEndian>
-class SEAL_Policy : public AdditiveCipherConcretePolicy<word32, 1024>, public SEAL_Info<B>
+class SEAL_Policy : public AdditiveCipherConcretePolicy<word32, 256>, public SEAL_Info<B>
 {
 public:
 	unsigned int IVSize() const {return 4;}
diff --git a/strciphr.h b/strciphr.h
index 2a297bba..8b3c9aa5 100644
--- a/strciphr.h
+++ b/strciphr.h
@@ -30,6 +30,7 @@
 
 #include "seckey.h"
 #include "secblock.h"
+#include "argnames.h"
 
 NAMESPACE_BEGIN(CryptoPP)
 
@@ -134,7 +135,7 @@ public:
 	typedef typename BASE::PolicyInterface PolicyInterface;
 
 protected:
-	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length);
+	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv);
 
 	unsigned int GetBufferByteSize(const PolicyInterface &policy) const {return policy.GetBytesPerIteration() * policy.GetIterationsToBuffer();}
 
@@ -226,7 +227,7 @@ public:
 protected:
 	virtual void CombineMessageAndShiftRegister(byte *output, byte *reg, const byte *message, unsigned int length) =0;
 
-	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length);
+	void UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv);
 
 	unsigned int m_leftOver;
 };
@@ -255,31 +256,38 @@ public:
 	SymmetricCipherFinalTemplate(const byte *key, unsigned int length)
 		{SetKey(key, length);}
 	SymmetricCipherFinalTemplate(const byte *key, unsigned int length, const byte *iv)
-		{SetKey(key, length); Resynchronize(iv);}
+		{SetKeyWithIV(key, length, iv);}
 
 	void SetKey(const byte *key, unsigned int length, const NameValuePairs &params = g_nullNameValuePairs)
 	{
 		ThrowIfInvalidKeyLength(length);
-		UncheckedSetKey(params, key, length);
+		UncheckedSetKey(params, key, length, GetIVAndThrowIfInvalid(params));
 	}
 
 	Clonable * Clone() const {return static_cast<SymmetricCipher *>(new SymmetricCipherFinalTemplate<BASE, INFO>(*this));}
 };
 
 template <class S>
-void AdditiveCipherTemplate<S>::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length)
+void AdditiveCipherTemplate<S>::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv)
 {
 	PolicyInterface &policy = AccessPolicy();
 	policy.CipherSetKey(params, key, length);
-	m_buffer.New(GetBufferByteSize(policy));
 	m_leftOver = 0;
+	m_buffer.New(GetBufferByteSize(policy));
+
+	if (IsResynchronizable())
+		policy.CipherResynchronize(m_buffer, iv);
 }
 
 template <class BASE>
-void CFB_CipherTemplate<BASE>::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length)
+void CFB_CipherTemplate<BASE>::UncheckedSetKey(const NameValuePairs &params, const byte *key, unsigned int length, const byte *iv)
 {
 	PolicyInterface &policy = AccessPolicy();
 	policy.CipherSetKey(params, key, length);
+
+	if (IsResynchronizable())
+		policy.CipherResynchronize(iv);
+
 	m_leftOver = policy.GetBytesPerIteration();
 }
 
diff --git a/validat1.cpp b/validat1.cpp
index 5619589e..c71a0f4b 100644
--- a/validat1.cpp
+++ b/validat1.cpp
@@ -1240,8 +1240,7 @@ bool ValidateSEAL()
 
 	cout << "\nSEAL validation suite running...\n\n";
 
-	SEAL<>::Encryption seal(key);
-	seal.Resynchronize(iv);
+	SEAL<>::Encryption seal(key, sizeof(key), iv);
 	unsigned int size = sizeof(input);
 	bool pass = true;