Tabbed: removed two little bugs due to the mess during the transition (my fault, sorry ;)

Tabbed.hs

@@ -92,7 +92,7 @@ data TabState =
     TabState { tabsWindows :: [(Window,Window)]
              , scr         :: Rectangle
              , fontS       :: FontStruct -- FontSet
-    } deriving ( Show , Read )
+    }
 
 data Tabbed a = 
     Tabbed (InvisibleMaybe TabState) TConf
@@ -139,7 +139,7 @@ handleMess (Tabbed (IJus st@(TabState {tabsWindows = tws}))  conf) m
     | Just ReleaseResources == fromMessage m = do d <- asks display
                                                   destroyTabs $ map fst tws
                                                   io $ freeFont d (fontS st)
-                                                  return Nothing
+                                                  return $ Just $ Tabbed INothin conf
 handleMess _ _  = return Nothing
 
 handleEvent :: TConf -> TabState -> Event -> X ()