diff --git a/src/server/shared/Database/QueryResult.h b/src/server/shared/Database/QueryResult.h
index fbe95b8c67..6f65239e6b 100755
--- a/src/server/shared/Database/QueryResult.h
+++ b/src/server/shared/Database/QueryResult.h
@@ -20,7 +20,7 @@
 #define QUERYRESULT_H
 
 #include <ace/Refcounted_Auto_Ptr.h>
-#include <ace/Null_Mutex.h>
+#include <ace/Thread_Mutex.h>
 
 #include "Field.h"
 #include "Log.h"
@@ -58,7 +58,7 @@ class ResultSet
         MYSQL_FIELD *m_fields;
 };
 
-typedef ACE_Refcounted_Auto_Ptr<ResultSet, ACE_Null_Mutex> QueryResult;
+typedef ACE_Refcounted_Auto_Ptr<ResultSet, ACE_Thread_Mutex> QueryResult;
 
 class PreparedResultSet
 {
@@ -103,7 +103,7 @@ class PreparedResultSet
 
 };
 
-typedef ACE_Refcounted_Auto_Ptr<PreparedResultSet, ACE_Null_Mutex> PreparedQueryResult;
+typedef ACE_Refcounted_Auto_Ptr<PreparedResultSet, ACE_Thread_Mutex> PreparedQueryResult;
 
 #endif