Offline IM replies

I've been having some problems in sending offline replies via email at times. I'm not positive but it seems to happen to me more when I have multiple IMs exchanged. This is the response I get:

This is the Postfix program at host data.agni.lindenlab.com.

I'm sorry to have to inform you that your message could not be
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                       The Postfix program

<mailtoim@data.agni.lindenlab.com> (expanded from
   <0fcc03e6-c3a2-ca03-7d3e-fd7bbec87a4b@im.agni.lindenlab.com>): Command died
   with status 100: "/opt/linden/indra/tools/mailglue/mailglue --grid=agni
   --system=im --rpcserver=http://xmlrpc.secondlife.com/cgi-bin/xmlrpc.cgi".
   Command output: Unsuccesful query from
   http://10.0.132.193:12035/xmlrpc/postmaster: Target agent not found.