Print Job Billing

[Gavin Young <gavin young clendons co nz>]

I realise this is not specifically a RHEL 4 question but I thought
people might have some suggestions for us considering our Print Server
is a Redhat Box.

We have multiple network printers connected to a Redhat Print Server
using cups. We are able to monitor which user is using which printer,
how many pages each printer has printed etc from the logs. What we would
like to do is know what customer the print job is for, for billing
purposes. Does anyone know of any open source solution that would allow
us to somehow tag a client and/or project number to every print job?
What do other companies do?

Any help or pointers would be much appreciated.

Gavin