Database error in vBulletin 3.8.6:

Invalid SQL:
DELETE FROM product WHERE productid = 'post_thanks';

MySQL Error : MySQL server has gone away
Error Number : 2006
Request Date : Wednesday, June 8th 2011 @ 06:23:26 AM
Error Date : Wednesday, June 8th 2011 @ 06:24:03 AM
Script :xxxxxxx /vb/admincp/plugin.php?do=productkill
Referrer :xxxxxxx /vb/admincp/plugin.php?do=productdelete&productid=post_thanks& s=
IP Address : xxxxxxx
Username : xxxxxxx
Classname : vB_Database
MySQL Version