diff --git a/rfb/SFileTransfer.cxx b/rfb/SFileTransfer.cxx
index 9161fff..0a8b40e 100644
--- a/rfb/SFileTransfer.cxx
+++ b/rfb/SFileTransfer.cxx
@@ -199,6 +199,9 @@
       }
     }
   }
+  // FIXME: For the next line, gcc says:
+  //        warning: deleting `void *' is undefined
+  //        Perhaps it should not be `void *' at all.
   delete [] pUploadData;
   return true;
 }
diff --git a/rfb/SFileTransfer.h b/rfb/SFileTransfer.h
index 62bed40..51a4928 100644
--- a/rfb/SFileTransfer.h
+++ b/rfb/SFileTransfer.h
@@ -39,9 +39,9 @@
   {
   public:
     SFileTransfer(network::Socket *sock);
-    ~SFileTransfer();
+    virtual ~SFileTransfer();
 
-	bool processMessages(int type);
+    bool processMessages(int type);
     bool sendFileDownloadPortion();
 
   protected:
diff --git a/rfb/SFileTransferManager.cxx b/rfb/SFileTransferManager.cxx
index d8b231a..999a079 100644
--- a/rfb/SFileTransferManager.cxx
+++ b/rfb/SFileTransferManager.cxx
@@ -52,4 +52,4 @@
 {
   while(!m_lstFTObjects.empty())
     delete m_lstFTObjects.front();
-}
\ No newline at end of file
+}
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);
diff --git a/rfb_win32/SFileTransferManagerWin32.h b/rfb_win32/SFileTransferManagerWin32.h
index b98de4f..ed1f997 100644
--- a/rfb_win32/SFileTransferManagerWin32.h
+++ b/rfb_win32/SFileTransferManagerWin32.h
@@ -36,8 +36,8 @@
     {
     public:
       SFileTransferManagerWin32();
-      ~SFileTransferManagerWin32();  
-      
+      virtual ~SFileTransferManagerWin32();
+
       void processDownloadMsg(MSG msg);
 
       virtual SFileTransfer *createObject(network::Socket *sock);
diff --git a/rfb_win32/SFileTransferWin32.h b/rfb_win32/SFileTransferWin32.h
index f4c87ea..5f682a4 100644
--- a/rfb_win32/SFileTransferWin32.h
+++ b/rfb_win32/SFileTransferWin32.h
@@ -38,7 +38,7 @@
     {
     public:
       SFileTransferWin32(network::Socket *sock);
-      ~SFileTransferWin32();
+      virtual ~SFileTransferWin32();
 
       bool processDownloadCallback();
       virtual bool initDownloadCallback();