outgoing address compromised

I have 2 issues with the compromise of an outgoing email alias for one of my
groups.

First, how could someone get that address? I have ,nobody after
grpname-outgoing in the list alias.

Second, how can I recover so my group members who have poor spam filters
don't get the spam?

-- 
karl
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 _/   _/ arl _/_/_/  _/ earson    [email protected]
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Senior Consulting Sys/DB Analyst
http://consulting.ourldsfamily.com
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 My Thoughts on Terrorism In America right after 9/11/2001:
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 A right is not what someone gives you; it's what no one can take from you.
 -Ramsey Clark
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