While installing Mailman in October, 2012, the following error was ocurre when email was sent:

<pre>
Oct 25 08:18:01 2012 (22827) Delivery exception: unbound method rejection_notice() must be called with ImplicitDestination instance as first argument (got MailList instance instead)
Oct 25 08:18:01 2012 (22827) Traceback (most recent call last):
  File "/home/mailman_6/Mailman/Handlers/HandlerAPI.py", line 82, in do_pipeline
    func(mlist, msg, msgdata)
  File "/home/mailman_6/Mailman/Handlers/Hold.py", line 182, in process
    hold_for_approval(mlist, msg, msgdata, ImplicitDestination)
  File "/home/mailman_6/Mailman/Handlers/Hold.py", line 217, in hold_for_approval
    msgdata['rejection-notice'] = exc.rejection_notice(mlist)
TypeError: unbound method rejection_notice() must be called with ImplicitDestination instance as first argument (got MailList instance instead)
</pre>

<p>See <a href="http://grokbase.com/t/python/mailman-users/077aw92y93/error-when-sending-from-an-unsubscribed-address">http://grokbase.com/t/python/mailman-users/077aw92y93/error-when-sending-from-an-unsubscribed-address</a>, which suggests the problem is the version of Python.</p>

<p>Line 82<code>/home/mailman_6/Mailman/Handlers/HandlerAPI.py</code> 
is marked below:</p>
<pre>
def do_pipeline(mlist, msg, msgdata, pipeline):
    while pipeline:
        modname = pipeline.pop(0)
	mod = __import__('Mailman.Handlers.' + modname)
        func = getattr(getattr(getattr(mod, 'Handlers'), modname), 'process')
        try:
            pid = os.getpid()
 ------&gt; func(mlist, msg, msgdata)
</pre>
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