2.6.1 blog hacked by sponsorsforblogs

my wp 2.6.1 blog just got hacked, and not sure what was done or how to get rid of it.

found out by referral in my stats program, this page here which i didn’t create.

http://adultaddstrengths.com.sponsorsforblogs.com/

they basically say This is special offer for adultaddstrengths.com owner, Find sponsors for your blog, and ask you to fill out an email form.

I saw on one other post that possibly the wordpress automatic upgrade plugin might be insecure so i deleted it but the post is still there and I don’t know how they got in, what they added or how to delete/disinfect my blog.

I saw the same hack on another site listed on this thread here,

http://groups.google.com/group/blogger-help-howdoi/browse_thread/thread/bfd39577f4162a5f/ee4ee1d8f117f588?lnk=raot

but unfortunately no answer. when i clicked through that persons email signup with a fake email address I got this page

“Thanks for signing. We sent confirmation link to your email, please check your inbox.

We will contact with you shortly when our sponsorship network will start. If you have any question, feel free & send me an email to kamil.przeorski@gmail.com”

If the guy who did it was kamil.przeorski@gmail.com and I’m not sure that it is, this is his site
http://przeor.com/ and his wordpress blog http://przeor.com/blog/

any suggestions?