bob@foo.com
joe@foo.com
jane@foo.com

##</code><code>##

push @{ $user_hash{$dlist_name} }, $user_email;

##</code><code>##

dlist@foo.com => jane@foo.com
dlist@foo.com => bob@foo.com
dlist@foo.com => joe@foo.com

##</code><code>##

sales@foo.com => joe@foo.com