I am soon to migrate a number of websites (each with its own domain)
to a new web hosting package. My old package (a Linux reseller account
with http://www.webfusion.com) let me place a .procmailrc in the root
of 'advanced' hosting accounts which would apply to the 'default'
e-mail account (i.e. domain@domain.com) for that domain . However I'm
now moving to their VPS (Virtual Private Server) solution where
Virtuozzo is used to 'virtualise' the Linux server. This solution no
longer has the concept of 'default' mail accounts and I can't work out
how to associate a .procmailrc file with a mail account. I've tried
putting it in the home directory of a domain and setting up a mailbox
domain@domain.com or user@domain.com but it had no effect. The server
uses qmail and CourierIMAP and obviously has Procmail available.

What do I need to do to associate a .procmailrc file to an e-mail address
(one per domain is enough, more is great) on a domain?

I have root shell access to the server and run any requested commands
to try and find the solution.

Thanks,
Geoff