diff --git a/ChangeLog b/ChangeLog
index 98701816..cefa475c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -39,6 +39,7 @@ John Emmas
 2011-11-24 Stephane Letz  <letz@grame.fr>
 
 	* Dynamic port management in JACK/CoreMidi bridge.
+	* Correct jack_client_create_thread (when realtime in on).
 
 2011-11-21 Stephane Letz  <letz@grame.fr>
 
diff --git a/common/JackAPI.cpp b/common/JackAPI.cpp
index 7f0f56d2..709be6c6 100644
--- a/common/JackAPI.cpp
+++ b/common/JackAPI.cpp
@@ -1776,7 +1776,14 @@ LIB_EXPORT int jack_client_create_thread(jack_client_t* client,
 #ifdef __CLIENTDEBUG__
     JackGlobals::CheckContext("jack_client_create_thread");
 #endif
-    return JackThread::StartImp(thread, priority, realtime, routine, arg);
+    JackEngineControl* control = GetEngineControl();
+    int res = JackThread::StartImp(thread, priority, realtime, routine, arg);
+    return (res == 0)
+        ? ((realtime ? JackThread::AcquireRealTimeImp(*thread, priority,
+            GetEngineControl()->fPeriod,
+            GetEngineControl()->fComputation,
+            GetEngineControl()->fConstraint) : res))
+        : res;
 }
 
 LIB_EXPORT int jack_drop_real_time_scheduling(jack_native_thread_t thread)