small fix in queuePutFirst

src/queue/put_first.c

@@ -31,6 +31,7 @@ TR_queuePutFirst(TR_Queue this, void * msg)
 	this->first       = TR_new(TR_Queue);
 	this->first->next = current_first;
 	this->first->msg  = msg;
+	this->last        = this->last ? this->last : this->first;
 	this->nmsg++;
 }