[exim] Looking for a sample configuration

Does anyone here use system groups to determine what domains are valid
for a system user to receive mail through? I am hosting nine domains on
a single system, and am looking for a simple way to allow a given user
to receive email through a defined subset of the domains. (I'm not yet
worrying about the consideration that I want to have one user name on
half the domains and another on the other half...)

Thanks,
Jim
-- 
Jim Trigg, Lord High Everything Else  O-      /"\
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