Index: jackrabbit-core/src/main/java/org/apache/jackrabbit/core/security/user/UserManagerImpl.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>MacRoman
===================================================================
--- jackrabbit-core/src/main/java/org/apache/jackrabbit/core/security/user/UserManagerImpl.java	(revision 1355043)
+++ jackrabbit-core/src/main/java/org/apache/jackrabbit/core/security/user/UserManagerImpl.java	(revision )
@@ -1131,7 +1131,10 @@
     public void loggedOut(SessionImpl session) {
         // and logout the session unless it is the logged-out session itself.
         if (session != this.session) {
+            // avoid potential race condition during shutdown (JCR-3246)
+            if (this.session.isLive()) {
-            this.session.logout();
+                this.session.logout();
+            }
         }
     }