From Mathias Froehlich, "Tha attached change adapt previous attemps to get our application using osg

through microsofts application verifier. The current change should work a
little better ...
The change is based on rev 10605."

src/OpenThreads/win32/Win32Thread.cpp

@@ -205,7 +205,10 @@ namespace OpenThreads {
 
 Thread* Thread::CurrentThread()
 {
-    return (Thread* )TlsGetValue(Win32ThreadPrivateData::TLS.getId());
+    DWORD ID = Win32ThreadPrivateData::TLS.getId();
+    if (ID == TLS_OUT_OF_INDEXES)
+        return 0;
+    return (Thread* )TlsGetValue(ID);
 }
 
 //----------------------------------------------------------------------------