diff --git a/include/wx/thread.h b/include/wx/thread.h
index d4af63db35..7e575b2f1e 100644
--- a/include/wx/thread.h
+++ b/include/wx/thread.h
@@ -368,8 +368,12 @@ public:
 
     // Get the thread ID - a platform dependent number which uniquely
     // identifies a thread inside a process
-    unsigned long GetId() const;
-
+#ifdef __VMS
+   unsigned long long GetId() const;
+#else
+   unsigned long GetId() const;
+#endif
+   
     // called when the thread exits - in the context of this thread
     //
     // NB: this function will not be called if the thread is Kill()ed
diff --git a/src/unix/threadpsx.cpp b/src/unix/threadpsx.cpp
index 8cebd7d212..ccec6bbc2e 100644
--- a/src/unix/threadpsx.cpp
+++ b/src/unix/threadpsx.cpp
@@ -743,8 +743,12 @@ void wxThreadInternal::Wait()
         wxMutexGuiLeave();
 
     bool isDetached = m_isDetached;
-    long id = (long)GetId();
-    wxLogTrace(TRACE_THREADS, _T("Starting to wait for thread %ld to exit."),
+#ifdef __VMS
+   long long id = (long long)GetId();
+#else
+   long id = (long)GetId();
+#endif
+   wxLogTrace(TRACE_THREADS, _T("Starting to wait for thread %ld to exit."),
                id);
 
     // wait until the thread terminates (we're blocking in _another_ thread,
@@ -1105,9 +1109,15 @@ unsigned int wxThread::GetPriority() const
     return m_internal->GetPriority();
 }
 
+#ifdef __VMS
+unsigned long long wxThread::GetId() const
+{
+    return (unsigned long long)m_internal->GetId();
+#else
 unsigned long wxThread::GetId() const
 {
     return (unsigned long)m_internal->GetId();
+#endif
 }
 
 // -----------------------------------------------------------------------------