"hmm....that sucks" Agreed !!
I had a bad experience with a "host" company which wouldn't allow more than 1 user on the MySQL database and it had to have full permission..(like hell I wasn't happy!)
I'm not sure if I can post the company I'm using atm ?? (but I do it anyway!
http://www.diyhost.co.uk/) now they are really helpfull and you get EVERYTHING working!
You can't seriously be asked to workout php without $_POST and $_SESSION -