diff --git a/src/kernel/qthread_unix.cpp b/src/kernel/qthread_unix.cpp
index 6a6f81b7..1050512a 100644
--- a/src/kernel/qthread_unix.cpp
+++ b/src/kernel/qthread_unix.cpp
@@ -183,6 +183,9 @@ void TQThreadInstance::finish( void * )
 void TQThreadInstance::finishGuiThread(TQThreadInstance *d) {
     TQThreadStorageData::finish( d->thread_storage );
     d->thread_storage = 0;
+
+    // Let all others (namely TQRegExp) know that the main thread is no longer alive
+    setCurrentThread(0);
 }
 
 TQMutex *TQThreadInstance::mutex() const