eror after upgrade

[havard20009]

Database error in vBulletin 4.0.1:

Invalid SQL:

(SELECT 'package' AS classtype, package.packageid AS typeid, package.packageid AS packageid,
package.productid AS productid, if(package.productid = 'vbulletin', 1, product.active) AS enabled,
package.class AS class, -1 as isaggregator
FROM package AS package
LEFT JOIN product AS product
ON product.productid = package.productid
WHERE product.active = 1
OR package.productid = 'vbulletin'
)

UNION

(SELECT 'contenttype' AS classtype, contenttypeid AS typeid, contenttype.packageid AS packageid,
1, 1, contenttype.class AS class , contenttype.isaggregator
FROM contenttype AS contenttype
INNER JOIN package AS package ON package.packageid = contenttype.packageid
LEFT JOIN product AS product ON product.productid = package.productid
WHERE product.active = 1
OR package.productid = 'vbulletin' );

MySQL Error : Illegal mix of collations (latin1_general_ci,IMPLICIT) and (cp1251_general_ci,IMPLICIT) for operation '='
Error Number : 1267
Request Date : Thursday, January 14th 2010 @ 02:54:27 AM
Error Date : Thursday, January 14th 2010 @ 02:54:28 AM
Script :
Referrer :
IP Address : 188.158.193.241
Username : EMO
Classname : vB_Database
MySQL Version : 5.0.85-community-log

what can i do ?

--------------- Added [DATE]1263478516[/DATE] at [TIME]1263478516[/TIME] ---------------

any help ?