diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/CommitCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/CommitCommand.java
index d0a794789..3b3baf5a1 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/CommitCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/CommitCommand.java
@@ -323,8 +323,14 @@ private void checkIfEmpty(RevWalk rw, ObjectId headId, ObjectId indexTreeId)
 	private void sign(CommitBuilder commit) throws ServiceUnavailableException,
 			CanceledException, UnsupportedSigningFormatException {
 		if (gpgSigner == null) {
-			throw new ServiceUnavailableException(
-					JGitText.get().signingServiceUnavailable);
+			gpgSigner = GpgSigner.getDefault();
+			if (gpgSigner == null) {
+				throw new ServiceUnavailableException(
+						JGitText.get().signingServiceUnavailable);
+			}
+		}
+		if (signingKey == null) {
+			signingKey = gpgConfig.getSigningKey();
 		}
 		if (gpgSigner instanceof GpgObjectSigner) {
 			((GpgObjectSigner) gpgSigner).signObject(commit,
@@ -659,12 +665,6 @@ private void processOptions(RepositoryState state, RevWalk rw)
 			signCommit = gpgConfig.isSignCommits() ? Boolean.TRUE
 					: Boolean.FALSE;
 		}
-		if (signingKey == null) {
-			signingKey = gpgConfig.getSigningKey();
-		}
-		if (gpgSigner == null) {
-			gpgSigner = GpgSigner.getDefault();
-		}
 	}
 
 	private boolean isMergeDuringRebase(RepositoryState state) {