VTMusic - 2006-05-30

I've created a backup user with Global privileges for Select and Lock Tables; and even specifically assigned that privilege for the 'information_schema' database yet am still getting an error when running AutoMySQLBackup:

mysqldump: Got error: 1044: Access denied for user 'backupuser'@'localhost' to database 'information_schema' when using LOCK TABLES

Any suggestions for what I might try next?  Thanks in advance.