Database error in vBulletin 3.8.4:

Invalid SQL:
INSERT INTO album
    (userid, title, description, state, createdate)
VALUES
    (5, 'wdw', 'dwdwdw', 'public', 1260542856);

MySQL Error   : Duplicate entry '0' for key 1
Error Number  : 1062
Request Date  : Friday, December 11th 2009 @ 04:47:36 PM
Error Date    : Friday, December 11th 2009 @ 04:47:36 PM
Script        : http://www.siteadi.com/album.php?do=updatealbum&u=5&albumid=0
Referrer      : http://www.siteadi.com/album.php?do=addalbum
IP Address    : 78.168.197.177
Username      : Beowulf78
Classname     : vB_Database
MySQL Version : 5.0.81-community