Forum MySQL Error : 137 when fixing table

[محروم.كوم]

Hello

I got this error when I try to upgrade my forum from 4.0.2 to 4.0.3


PHP Code:
Database error in vBulletin 4.0.2:

Invalid SQL:

ALTER TABLE post
ADD htmlstate ENUM ('off', 'on', 'on_nl2br') NOT NULL DEFAULT 'on_nl2br';

MySQL Error : 137 when fixing table
Error Number : -1
Request Date : Thursday, April 22nd 2010 @ 01:11:14 AM
Error Date : Thursday, April 22nd 2010 @ 01:12:02 AM
Script : http://www.mydomain.com/vb4/install/upgrade_403.php?step=1
Referrer : http://www.mydomain.com/vb4/install/upgrade_403.php

Classname : vB_Database

Any idea to fix it?

Thanks __DEFINE_LIKE_SHARE__