MYSQL Database Error- Can someone help me?

[dominick32]

Can someone let me know why some users are causing this administrative database e-mail to me:

Database error in vBulletin 3.0.3:

Invalid SQL: 
                SELECT user.avatarid, user.avatarrevision, avatarpath, NOT ISNULL(avatardata) AS hascustom, customavatar.dateline
                FROM user AS user
                LEFT JOIN avatar AS avatar ON avatar.avatarid = user.avatarid
                LEFT JOIN customavatar AS customavatar ON customavatar.userid = user.userid
                WHERE user.userid = 
mysql error: You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 5

mysql error number: 1064

Thanks,
Dom

[Xenon]

WHERE user.userid =

well, there should be a value behind that =

it's most likely you installed a hack incorrectly, or a hack you installed is buggy.