Server error or vbulletin?

[محروم.كوم]

Hello, what type of error is this...

I m getting hundreds of emails like this per day. Is it a problem with my hosting or something is wrong with vbulletin. Just because my other sites are working fine, problem is in vbulletin only.
Code:
Database error in vBulletin :

Invalid SQL:
SELECT varname, value, datatype FROM vb_setting;

MySQL Error : MySQL server has gone away
Error Number : 2006
Request Date : Wednesday, June 3rd 2009 @ 05:27:45 PM
Error Date : Wednesday, June 3rd 2009 @ 05:29:26 PM
Script : http://www.nannu.info/forum/showthread.php?t=4588
Referrer : http://www.nannu.info/
IP Address : 94.161.109.9
Username :
Classname : vB_Database
MySQL Version :
Help plzzzz __DEFINE_LIKE_SHARE__