Hmail Server Configuration and Spam blocking guru required

URGENT! - We require someone with an excellent understanding of setting up and configuring Hmail Server on our office based Windows 7 system being used as the server.

We currently have two domain names need configuring on this server but have tried ourselves but cannot get this working.
The MX and DNS entries are all (apparantly) setup correctly.

If you telnet to the server, the server receives the mail fine on port 25 but then nothing.

Currently, the server seems to be being used as some kind of mail relay by a hacker so this needs sorting out.
We are using the server as a newsletter sender and have some PHP based newsletter software ready and waiting to send out but cant until incoming emails are being redirected to the correct POP3 accounts setup within Hmail server.

This is an immediate requirement and a candidate will be chosen within the next 12 hours so act fast.