Well, I have this same problem with my hosting from time to time too. They update something and then php mail doesn't work anymore or some crucial library is getting missing. But usually at the instant I complain they put themselves to work and they fix them.
It's a shame that the whole MamboPortal have to move servers just because of a tiny problem like php mails, because this is a solvable problem, but well, if the server doesn't provide the service they might, is better moving and forget any problem.
Note: Actually, I have not the right to complain about my server since is a free webhosting.
