Only the part before the AT-sign is case-sensitive.  There are both good
and bad reasons to have multiple subscriptions.  Having multiples is not
necessarily bad.  It IS difficult to manipulate subscripton options
though for a single subscription when multiple case-sensitive ones exist.

If the problem is an abuse issue, then SET listname REVIEW (or perhaps
NOPOST).  Or exclude via wild-card list definition FILTERing.

At 11:56 09/17/2001 Monday, David Hopkins wrote:
 >How do you deal with a subscriber who subscribes two or more times using
 >different CASE in their mail address?
 >
 >For example, Joe Blow signed up with:
 >
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