I am going through the same problem with Ixwebhosting. I made so many security mistakes that it is hard to place the blame on the host but I did go ahead and request to be moved to the newest cpanel which gave me php5 and new ip addresses. I had backups and used the opportunity to get a clean start an do a better job of hardening my sites as well as my back up procedures. It sucks but sometimes we have to learn the hard way.
ps.
There are several good post and articles on how to harden WordPress.
