[Exim] Maildir (qmail-style) with virtual domain

Hi all,

Does any of you know a POP3/IMAP server which supports
both Qmail's maildir system and the name-based virtual
domain?

I've looked for such a popper, but nothing found.
Does that mean I should 've to work with source coding?

# I think i have to set up maildir system, because
# one of the users currently have 200MB+ mbox... wow!

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Norihisa Washitake <wassy@???>
System Engineer at GENS Co., Ltd. Japan.