Have you upgraded your version of php from 4 to 5? Upgrades now require php 5. If it isn't available on your host (although most of them it is) I would simply roll back to the earlier version.
It would be odd to have a virus in your WordPress application. I'm going to move this to the php forum. Maybe one of those geniuses there will know the right questions to ask you to pick up on what is causing your fatal error.
Bookmarks