Postfix, Mail Scanner and Mailscanner-mrtg

[Phuntsho Ugyel]

Hi
Am running postfix and would really like to have an mrtg graph of mails, 
spams etc that is being processed by my mail server.

I generally try not to flood mailing lists but i could not find anything 
when trying to google. So here are the doubts that i have.

1. Can mailscanner-mrtg be used on a mail server running postfix? if 
yes, any documentations?
2. Does the mailscanner-mrtg and postfix have to be on the same server? 
Can they be on different machines? [would like them to be on different 
machines]

If it is not possible, then could someone please suggest an alternative.

Thanking you in advance
Phuntsho