Moving IMAP Maildir to another user

A little recipe to move a user's IMAP mails to another user. (Tested on the Courier IMAP server on Debian).

Useful in situations like John leaving the company and Bob needing to have access to John's old emails.

olduser=john; newuser=bob
maildirmake -f $olduser /home/$newuser/Maildir/
cd /home/$olduser/Maildir/
for d in * ; do \
    cp -pr "$d" "/home/$newuser/Maildir/.$olduser/"; \
done
echo "INBOX.$olduser"  >>/home/$newuser/Maildir/courierimapsubscribed
for d in .??*; do \
    cp -pr "$d" "/home/$newuser/Maildir/.$olduser$d"; \
    echo "INBOX.$olduser$d" >>/home/$newuser/Maildir/courierimapsubscribed; \
done
chown -R $newuser /home/$newuser/Maildir

(Beware that if John had a folder with a one-letter name, that one will not be copied. It's because "for d in .*" would do a mess trying to copy "." and "..". So line 6 uses "for d in .??*" instead.)