Vbulletin 4.0 dan 3.8 e nasıl dönerim?

Database error in vBulletin 4.0.0 Beta 3:

Invalid SQL:
SHOW KEYS FROM word;

MySQL Error   : Table 'saksafon_filmindir.word' doesn't exist

Database error in vBulletin 4.0.0 Beta 3:

Invalid SQL:

				SELECT dateline, thumbnail_dateline, filename, filesize, visible, attachmentid, counter,
					IF(thumbnail_filesize > 0, 1, 0) AS hasthumbnail, thumbnail_filesize,
					attachmenttype.thumbnail AS build_thumbnail, attachmenttype.newwindow
				FROM attachment AS attachment
				LEFT JOIN attachmenttype AS attachmenttype USING (extension)
				WHERE posthash = 'invalid posthash'
					AND userid = 1
				ORDER BY attachmentid;

MySQL Error   : Unknown column 'extension' in 'from clause'