[Exim] lokal user with uppercase-logins wont be delivered

moin *

im wondering about exim, he doesnt deliver right (or i made a mistake :)
if i create a lokal user, which has upper-case letters in his login (like
"MrBig"), exim wont deliver any mails for him (i tried "mrbig@localhost"
and "MrBig@localhost").
a mail to an other user, who has only lower-case letters in his login (like
"smith") is deliverd correct, even i wrote the to-part in upper-case (i
tried "SMITH@localhost")


so, what im doing wrong?

frank

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