diff --git a/rfb/SFileTransferManager.h b/rfb/SFileTransferManager.h
index 4ee1406..fe81644 100644
--- a/rfb/SFileTransferManager.h
+++ b/rfb/SFileTransferManager.h
@@ -36,7 +36,7 @@
   {
   public:
     SFileTransferManager();
-    ~SFileTransferManager();
+    virtual ~SFileTransferManager();
 
     virtual SFileTransfer *createObject(network::Socket *sock) = 0;
     void destroyObject(SFileTransfer *pFT);