Index: src/main/java/org/apache/jackrabbit/core/state/SessionItemStateManager.java
===================================================================
--- src/main/java/org/apache/jackrabbit/core/state/SessionItemStateManager.java	(revision 948355)
+++ src/main/java/org/apache/jackrabbit/core/state/SessionItemStateManager.java	(working copy)
@@ -337,8 +337,6 @@
         removeListener(hierMgr);
         // discard all transient changes
         disposeAllTransientItemStates();
-        // dispose our (i.e. 'local') state manager
-        stateMgr.dispose();
     }
 
     //< more methods for listing and retrieving transient ItemState instances >
Index: src/main/java/org/apache/jackrabbit/core/WorkspaceImpl.java
===================================================================
--- src/main/java/org/apache/jackrabbit/core/WorkspaceImpl.java	(revision 948355)
+++ src/main/java/org/apache/jackrabbit/core/WorkspaceImpl.java	(working copy)
@@ -178,6 +178,9 @@
             obsMgr.dispose();
             obsMgr = null;
         }
+        // remove hierarchy manager as listener to avoid
+        // unnecessary work during stateMgr.dispose()
+        stateMgr.removeListener(hierMgr);
         stateMgr.dispose();
     }