Issue1226

def add_channel(self, map=None):
        #self.log_info('adding channel %s' % self)
        if map is None:
            if hasattr(self, '_map'):
                map = self._map
                del self._map
            else:
                map = socket_map
        if not hasattr(self, '_fileno'):
            self._fileno = self.socket.fileno()
        map[self._fileno] = self


The line "del self._map" breaks pyftpdlib [1] and, I presume, all other
other applications built on top of asyncore not using a custom socket_map.
There's really no reason to delete that attribute.

[1] http://code.google.com/p/pyftpdlib/

This bug refers solely to the previous version of asyncore.
I have just checked in a new version, which is the cpython 2.5 asyncore
ported to jython 2.5.
Therefore this bug is no longer relevant; closing as "out of date".