possible courier bug?

[Igor Gueths]

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Hi all. I just recently set up my girlfriend's e-mail account on my 
system. The problem is that the first character of her username is upper 
case instead of lower case. When I tried sending a message from a remote 
machine I have access to to her e-mail address (changed the first 
character to lower case) to see if Courier would handle the case 
propperly, Courier returned a 550 User unknown message to the relaying 
server that was trying to deliver mail. Now someone correct me if I am 
wrong, but I seem to recall that the SMTP RFC says something to the 
effect that the protocol is supposed to ignore the case? In other words, 
be case insensitive? Does anyone know if this is perhaps a bug in 
Courier, or is the behavior I am experiencing normal? Thanks!
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