Index: libjava/include/posix-threads.h
===================================================================
--- libjava/include/posix-threads.h	(revision 196601)
+++ libjava/include/posix-threads.h	(working copy)
@@ -79,7 +79,7 @@
 inline int
 _Jv_MutexCheckMonitor (_Jv_Mutex_t *mu)
 {
-  return (mu->owner != pthread_self());
+  return (pthread_equal(mu->owner, pthread_self()) == 0);
 }
 
 // Type identifying a POSIX thread.