diff --git a/platform/vcs-impl/src/com/intellij/openapi/vcs/actions/AnnotateToggleAction.java b/platform/vcs-impl/src/com/intellij/openapi/vcs/actions/AnnotateToggleAction.java
index 380b513b09c7..7c628e48a16c 100644
--- a/platform/vcs-impl/src/com/intellij/openapi/vcs/actions/AnnotateToggleAction.java
+++ b/platform/vcs-impl/src/com/intellij/openapi/vcs/actions/AnnotateToggleAction.java
@@ -310,7 +310,7 @@ public class AnnotateToggleAction extends ToggleAction implements DumbAware, Ann
           final int size = bgColors.size();
           bgColors.put(author, BG_COLORS[size < length ? size : size % length]);
         }
-        if (!revNumbers.containsKey(revNumber)) {
+        if (revNumber != null && !revNumbers.containsKey(revNumber)) {
           revNumbers.put(revNumber, bgColors.get(author));          
         }
     }