A staff member pointed me towards your thread. I believe I can help.
I can offer you the features you require to run Gossamer Mail as well as mod_perl if your site has quite a bit of traffic.
Disk space incurs a minimal fee (although it would be good to know what kind of space you'd need), the bandwidth usage is more of a concern, price wise. Do you know what amount of bandwidth you'd need?
You can email email@example.com if you want.