Recently we moved a vbulletin from one server to another, and everything seems to be working perfectly except for one single thing. When you're in a thread, and you click on the 'search' button (search per username) we get a mySQL error that's:

Database error in vBulletin 2.2.9:
Invalid SQL: SELECT COUNT(*) AS posts FROM post
WHERE post.visible=1 AND post.threadid= AND 1=1 AND post.userid='10'
mysql error: You have an error in your SQL syntax near 'AND 1=1 AND post.userid='10'' at line 2
mysql error number: 1064
Date: Sunday 23rd of February 2003 10:22:02 PM

Is there any way to fix this?