Get rid of WordPress 2.1.1
From the official site (www.wordpress.org) :
“… The issue was investigated, and it appeared that the 2.1.1 download had been modified from its original code. We took the website down immediately to investigate what happened.
It was determined that a cracker had gained user-level access to one of the servers that powers wordpress.org, and had used that access to modify the download file. We have locked down that server for further forensics, but at this time it appears that the 2.1.1 download was the only thing touched by the attack. They modified two files in WP to include code that would allow for remote PHP execution…”
So if you downloaded WordPress 2.1.1 within the past 4-5 days, your files may include a security exploit that was added by a cracker, and you should upgrade all of your files to 2.1.2 immediately.