diff --git a/TestVectors/all.txt b/TestVectors/all.txt
index 776e0099..776bd2da 100644
--- a/TestVectors/all.txt
+++ b/TestVectors/all.txt
@@ -9,6 +9,8 @@ Test: TestVectors/whrlpool.txt
 Test: TestVectors/dlies.txt
 Test: TestVectors/dsa.txt
 Test: TestVectors/dsa_1363.txt
+#Test: TestVectors/dsa_rfc6979.txt
+#Test: TestVectors/ecdsa_rfc6979.txt
 Test: TestVectors/esign.txt
 Test: TestVectors/hmac.txt
 Test: TestVectors/nr.txt
diff --git a/datatest.cpp b/datatest.cpp
index 8c22cb5f..ccc61c6e 100644
--- a/datatest.cpp
+++ b/datatest.cpp
@@ -286,8 +286,13 @@ void TestSignatureScheme(TestData &v)
 	}
 	else if (test == "DeterministicSign")
 	{
-		SignalTestError();
-		assert(false);	// TODO: implement
+		// This test is specialized for RFC 6979. The RFC is a drop-in replacement
+		// for DSA and ECDSA, and access to the seed or secret is not needed. If
+		// additional determinsitic signatures are added, then the test harness will
+		// likely need to be extended.
+		SignerFilter f(GlobalRNG(), *signer, new HexEncoder(new FileSink(cout)));
+		StringSource ss(GetDecodedDatum(v, "Message"), true, new Redirector(f));
+		SignalTestFailure();
 	}
 	else if (test == "RandomSign")
 	{