vBulletin Database Error?

[KevinGupta]

What is this? I mean what should I do about this error? I don't even know why I am getting it?

I received this error in email via my forum:

Database error in vBulletin 4.0.1:

Invalid SQL:

SELECT COUNT(*) AS threads, SUM(IF(thread.lastpost > 1266667805 AND open <> 10, 1, 0)) AS newthread
FROM thread AS thread
WHERE forumid IN( )
AND thread.visible = 1;

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 ')
AND thread.visible = 1' at line 3
Error Number : 1064
Request Date : Saturday, February 20th 2010 @ 06:10:05 AM
Error Date : Saturday, February 20th 2010 @ 06:10:06 AM
Script : http://www."forum".com/forum/articles.php?c=33
Referrer : http://www."forum".com/forum/articles.php?c=33
IP Address : 195.xxx.xx.xxx
Username : Unregistered
Classname : vB_Database
MySQL Version :

This is the error that I get on the website when I click on the link that I received in email (above):

Warning: fetch_template() calls should be replaced by the vB_Template class. Template name: navbar in [path]/includes/functions.php on line 3893

Parse error: syntax error, unexpected T_STRING in /home/public_html/forum/articles.php(40) : eval()'d code on line 1

Warning: fetch_template() calls should be replaced by the vB_Template class. Template name: STANDARD_ERROR in [path]/includes/functions.php on line 3893

Parse error: syntax error, unexpected T_STRING in /home/public_html/forum/articles.php(73) : eval()'d code on line 1
Database error
Forum database has encountered a problem.

--------------------------------------------------------------------------------

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