diff --git a/pg/src/main/java/org/bouncycastle/openpgp/api/AbstractOpenPGPDocumentSignatureGenerator.java b/pg/src/main/java/org/bouncycastle/openpgp/api/AbstractOpenPGPDocumentSignatureGenerator.java
index 4111697472..241c8e1b2b 100644
--- a/pg/src/main/java/org/bouncycastle/openpgp/api/AbstractOpenPGPDocumentSignatureGenerator.java
+++ b/pg/src/main/java/org/bouncycastle/openpgp/api/AbstractOpenPGPDocumentSignatureGenerator.java
@@ -251,7 +251,7 @@ protected PGPSignatureGenerator initSignatureGenerator(
         }
 
         return Utils.getPgpSignatureGenerator(implementation, signingKey.getPGPPublicKey(),
-            unlockedKey.getPrivateKey(), parameters, null, null);
+            unlockedKey.getPrivateKey(), parameters, parameters.getSignatureCreationTime(), null);
     }
 
     private int getPreferredHashAlgorithm(OpenPGPCertificate.OpenPGPComponentKey key)
diff --git a/pg/src/main/java/org/bouncycastle/openpgp/api/OpenPGPKeyEditor.java b/pg/src/main/java/org/bouncycastle/openpgp/api/OpenPGPKeyEditor.java
index 5a7801bad1..5fd33e7276 100644
--- a/pg/src/main/java/org/bouncycastle/openpgp/api/OpenPGPKeyEditor.java
+++ b/pg/src/main/java/org/bouncycastle/openpgp/api/OpenPGPKeyEditor.java
@@ -262,7 +262,7 @@ public OpenPGPKeyEditor addSigningSubkey(PGPKeyPair signingSubkey,
 
         PGPPublicKey publicPrimaryKey = key.getPrimaryKey().getPGPPublicKey();
 
-        final PGPSignature backSig = Utils.getBackSignature(signingSubkey, backSigParameters, publicPrimaryKey, implementation, null);
+        final PGPSignature backSig = Utils.getBackSignature(signingSubkey, backSigParameters, publicPrimaryKey, implementation, backSigParameters.getSignatureCreationTime());
 
         updateKey(signingSubkey, bindingSigCallback, publicPrimaryKey, new Utils.HashedSubpacketsOperation()
         {