I have recently inherited a system using postfix and courier-imap (with mysql)
to deliver mail to virtual mail users. By this I mean mail recipients on web
domains which are hosted on this machine, but are not login accounts. Users
typically access their mail via Outlook Express. They would like to have
filtering that will deposit mail into different folders depending on various
criteria. It appears that maildrop will satisfy their needs, so I attempted to
install it. It does not appear to be running. Mail delivery worked both before
and after the changes. System particulars are:

RH release 7.2, kernel version 2.4.17 postfix - snapshot-20011008 courier-imap 1.3.11 mysql maildrop 1.3.5

I changed /etc/postfix/main.cf so that mailbox_command, mailbox_transport and
fallback_transport all = /usr/bin/maildrop

maildrop's config.h was modified to turn on SYSLOG and set DEFAULT_DEF, maildrop
was remade, and installed (unstripped).

/var/log/maillog shows entries only for postfix. No logs contain maildrop
entries. I find no evidence anywhere that postfix is trying to use maildrop.

Any help would be appreciated.