Very usefull commands of Qmail  :-

1. How to find the of mails in a queue:
/var/qmail/bin/qmail-qstat
2.How to see mails in queue:
/var/qmail/bin/qmail-qread

find /var/qmail/queue/ -name 1589415
less /var/qmail/queue/mess/0/1589415
3.How to clean queue Mails
qmail-remove -r -p “Banking” -i -v
qmail-remove -r -p mailer-daemon -i -v
qmail-remove -r -p bouncing -i -v
4.How to delete messages with a particular pattern in the subject line
/usr/local/psa/admin/bin/mailqueuemng -S”text”
5. To list remote message queue:
/usr/local/psa/admin/bin/mailqueuemng -R
6. list local message queue:
/usr/local/psa/admin/bin/mailqueuemng -L