Email Debacle PHP?

I am frustrated to say the least. For 4 days one of my clients emails have been compromised. After 2 days I recieved a message telling me that one of my PHP scripts was compormised and I should update them and be fine. I updated, then ended up removing everything but my wordpress install and he is still getting hundreds of emails. My wordpress in updated to 2.01. Any ideas? Dreamhost Support sure is not helping. I changed the password on the account? Any help would be very much appreciated.


“Compromised” how?