Installing NomadCF's Q-Sorter is easy as 123.
Steps Commands (based on redhat 7.2 and default installs)
1st We have to get the files we'll need. They can be found here.
2nd We need to ungip them. gzip -d Q-Sorter.tar.gz
3rd We have to untar them. tar -xf Q-Sorter.tar
4th We have to move the we dir we just untared into your Web dir. mv Q-Sorter /var/www/html/
5th we need to move the Q-Sorter.php into your qmail bin. mv /var/www/html/Q-Sorter/Q-Sorter.php /var/qmail/bin/
For vpopmail users: mv /var/www/html/Q-Sorter/Q-Sorter.php /home/vpopmail/bin/
6th we need to set the owner and group of Q-Sorter.php chown root.qmail /var/qmail/bin/Q-Sorter.php
For vpopmail users: Thier already set :)
7th we need to setup the table in the database mysql < /var/www/html/Q-Sorter/Q-Sorter_mysql.sql
8th remove the Q-Sorter_mysql.sql. (Just to safe) rm /var/www/html/Q-Sorter/Q-Sorter_mysql.sql
9th edit both Q-Sorter.php and filter.php and edit the user database stuff. vim /var/qmail/bin/Q-Sorter.php /var/www/html/Q-Sorter/filter.php

Time to make a choice You can do the into differnt ways.
Option How to
Preuser. edit .qmail inside every user home mail dir. and put this in it.
|/var/qmail/bin/Q-Sorter.php $RECIPIENT $HOME
Global edit .qmail-default inside each domain under /home/vpopmail/domains/ and put this in it.
|/home/vpopmail/bin/Q-Sorter.php $RECIPIENT $HOME

Thats it your done just login to http://YOURSERVER.whatever/Q-Sorter/
And set up your filters. (Remember if your using vpopmail. for username will be USER@DOMAIN.Whatever.