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);
 }
 
 //----------------------------------------------------------------------------

src/OpenThreads/win32/Win32ThreadPrivateData.h

@@ -71,18 +71,21 @@ public:
     struct TlsHolder{ // thread local storage slot
         DWORD getId()
         {
-            static bool initialized = false;
             if (!initialized) {
                 ID = TlsAlloc();
                 initialized = true;
             }
             return ID;
         }
+        TlsHolder() : ID(TLS_OUT_OF_INDEXES), initialized(false) {}
         ~TlsHolder(){
-            TlsFree(ID);
+            if (initialized)
+                TlsFree(ID);
+            ID = TLS_OUT_OF_INDEXES;
         }
     private:
         DWORD ID;
+        bool initialized;
     };
 
     static TlsHolder TLS;