Mb2md.pl is a Perl script that takes one or more Mbox format mailbox
files in a directory and convert them to Maildir format mailboxes.
Mb2md.pl does not only convert mailbox files into a Maildir but
also the /var/spool/mail/$USER mailspool file. It is smart enough
to not transfer a dummy message such as the UW IMAPD puts at the
start of Mbox mailboxes - and you could add your own search terms
into the script to make it ignore other forms of dummy first message.