* Gerald C. Simmons <simmons@darykon.cet.com> [020223 18:10]:
...
> Is there something in default Sendmail configuration that won't allow mixed
> case usernames?
> 
> Is there a way to set case-sensitivity?
...

see http://www.sendmail.org/faq/section4.html#4.17

You need to add the 'u' flag to the LOCAL mailer. 
Normally the LOCAL mailer translates all usernames to lowercase
before accessing the mailbox.

Simon.
-- 
Simon. Laule	netbsd@laule.de