diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
index 9ef1722d7..8d59cb47b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
@@ -531,7 +531,7 @@ public abstract class RefUpdate {
 		final String myName = getRef().getLeaf().getName();
 		if (myName.startsWith(Constants.R_HEADS)) {
 			Ref head = getRefDatabase().getRef(Constants.HEAD);
-			while (head.isSymbolic()) {
+			while (head != null && head.isSymbolic()) {
 				head = head.getTarget();
 				if (myName.equals(head.getName()))
 					return result = Result.REJECTED_CURRENT_BRANCH;