Merge trift2.:/MySQL/M50/merge-5.0

into  trift2.:/MySQL/M50/push-5.0

libmysqld/lib_sql.cc

@@ -590,7 +590,7 @@ void *create_embedded_thd(int client_flag)
   thd->set_time();
   thd->init_for_queries();
   thd->client_capabilities= client_flag;
-  thd->real_id= (pthread_t) thd;
+  thd->real_id= (pthread_t)thd->thread_id;
 
   thd->db= NULL;
   thd->db_length= 0;

sql/item_func.cc

@@ -3578,7 +3578,7 @@ longlong Item_func_release_lock::val_int()
   else
   {
 #ifdef EMBEDDED_LIBRARY
-    if (ull->locked && pthread_equal(current_thd->real_id,ull->thread))
+    if (ull->locked && (current_thd->real_id == ull->thread))
 #else
     if (ull->locked && pthread_equal(pthread_self(),ull->thread))
 #endif