app gives a misleading errormessage when a error while binding to
a port occures. This patch logs the error which actually has happended.
 --drt@un.bewaff.net - http://c0re.jp/
diff -u -r Twisted-0.15.0/twisted/internet/app.py Twisted/twisted/internet/app.py
--- Twisted-0.15.0/twisted/internet/app.py	Wed Jan 23 04:09:39 2002
+++ Twisted/twisted/internet/app.py	Fri Feb 15 22:35:05 2002
@@ -348,8 +348,8 @@
             for port in self.ports:
                 try:
                     port.startListening()
-                except socket.error:
-                    log.msg('port %s already bound' % port.port)
+                except socket.error, msg:
+                    log.msg('port %s: error: %s' % (port.port, msg[1]))
                     return
             for connector in self.connectors:
                 connector.startConnecting()