Index: /trunk/src/VBox/Main/MachineImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/MachineImpl.cpp	(revision 23944)
+++ /trunk/src/VBox/Main/MachineImpl.cpp	(revision 23945)
@@ -2049,6 +2049,9 @@
                                    IN_BSTR aId)
 {
-    LogFlowThisFunc(("aControllerName=\"%ls\" aControllerPort=%d aDevice=%d\n",
-                     aControllerName, aControllerPort, aDevice));
+    LogFlowThisFunc(("aControllerName=\"%ls\" aControllerPort=%d aDevice=%d aType=%d aId=\"%ls\"\n",
+                     aControllerName, aControllerPort, aDevice, aType, aId));
+
+    CheckComArgNotNull(aControllerName);
+    CheckComArgNotNull(aId);
 
     AutoCaller autoCaller(this);