--- a/src/share/classes/com/sun/corba/se/impl/orb/ORBImpl.java	Mon Nov 29 22:10:46 2010 -0800
+++ b/src/share/classes/com/sun/corba/se/impl/orb/ORBImpl.java	Wed Dec 01 16:46:18 2010 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -245,7 +245,14 @@
     // All access to resolver, localResolver, and urlOperation must be protected using
     // resolverLock.  Do not hold the ORBImpl lock while accessing
     // resolver, or deadlocks may occur.
-    private Object resolverLock ;
+    // Note that we now have separate locks for each resolver type.  This is due
+    // to bug 6980681 and 6238477, which was caused by a deadlock while resolving a
+    // corbaname: URL that contained a reference to the same ORB as the
+    // ORB making the call to string_to_object.  This caused a deadlock between the
+    // client thread holding the single lock for access to the urlOperation,
+    // and the server thread handling the client is_a request waiting on the
+    // same lock to access the localResolver.
+
 
     // Used for resolver_initial_references and list_initial_services
     private Resolver resolver ;
@@ -255,8 +262,14 @@
 
     // Converts strings to object references for resolvers and string_to_object
     private Operation urlOperation ;
+    private final Object urlOperationLock = new java.lang.Object() ;
 
     private CorbaServerRequestDispatcher insNamingDelegate ;
+    // resolverLock must be used for all access to either resolver or
+    // localResolver, since it is possible for the resolver to indirectly
+    // refer to the localResolver.  Also used to protect access to
+    // insNamingDelegate.
+    private final Object resolverLock = new Object() ;
 
     private TaggedComponentFactoryFinder taggedComponentFactoryFinder ;
 
@@ -396,7 +409,6 @@
             }
         };
 
-        resolverLock = new java.lang.Object() ;
 
         requestDispatcherRegistry = new RequestDispatcherRegistryImpl(
             this, ORBConstants.DEFAULT_SCID);
@@ -832,7 +844,7 @@
         if (str == null)
             throw wrapper.nullParam() ;
 
-        synchronized (resolverLock) {
+        synchronized (urlOperationLock) {
             org.omg.CORBA.Object obj = (org.omg.CORBA.Object)op.operate( str ) ;
             return obj ;
         }
@@ -1778,7 +1790,7 @@
      */
     public void setURLOperation( Operation stringToObject )
     {
-        synchronized (resolverLock) {
+        synchronized (urlOperationLock) {
             urlOperation = stringToObject ;
         }
     }
@@ -1788,7 +1800,7 @@
      */
     public Operation getURLOperation()
     {
-        synchronized (resolverLock) {
+        synchronized (urlOperationLock) {
             return urlOperation ;
         }
     }