@@ -1317,10 +1317,19 @@ class DotWidget(gtk.DrawingArea):

             [self.filter, '-Txdot'],

             stdin=subprocess.PIPE,

             stdout=subprocess.PIPE,

+            stderr=subprocess.PIPE,

             shell=False,

             universal_newlines=True

         )

-        xdotcode = p.communicate(dotcode)[0]

+        xdotcode, error = p.communicate(dotcode)

+        if p.returncode != 0:

+            dialog = gtk.MessageDialog(type=gtk.MESSAGE_ERROR,

+                                       message_format=error,

+                                       buttons=gtk.BUTTONS_OK)

+            dialog.set_title('Dot Viewer')

+            dialog.run()

+            dialog.destroy()

+            return False

         try:

             self.set_xdotcode(xdotcode)

         except ParseError, ex: