Mysql::Error: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8_general_ci,COERCIBLE)

Hi, I've got an error when I upload a record by iPhone with Chinese character.

Processing ScoresController#create (for 123.204.56.133 at 2009-08-04 16:19:52) [POST]
   Parameters: {"score"=>{"score"=>"79.60", "player_name"=>"一", "iphone_identifier"=>"6b194f783d645ba1a7c30c0e31b1b67300eb0a25"}, "product_id"=>"7"}
   ^[[4;35;1mSQL (0.1ms)^[[0m ^[[0mSET collation_database = 'utf8_general_ci' ^[[0m
   ^[[4;36;1mSQL (0.1ms)^[[0m ^[[0;1mSET collation_connection = 'utf8_general_ci' ^[[0m
7--- !map:HashWithIndifferentAccess
score: "79.60"
player_name: !binary |
   5LiA

iphone_identifier: 6b194f783d645ba1a7c30c0e31b1b67300eb0a25
   ^[[4;35;1mSQL (0.2ms)^[[0m ^[[0mSHOW VARIABLES LIKE 'collation_database'^[[0m
Collation: utf8_general_ci
   ^[[4;36;1mScore Load (0.0ms)^[[0m ^[[0;1mMysql::Error: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8_general_ci,COERCIBLE) for operation '=': SELECT * FROM
  `scores` WHERE (`scores`.`product_id` = '7' AND `scores`.`iphone_identifier` = '6b194f783d645ba1a7c30c0e31b1b67300eb0a25' AND `scores`.`player_name` = '一') LIMIT 1^[[0m

ActiveRecord::StatementInvalid (Mysql::Error: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8_general_ci,COERCIBLE) for operation '=': SELECT * FROM `scores` WHE
RE (`scores`.`product_id` = '7' AND `scores`.`iphone_identifier` = '6b194f783d645ba1a7c30c0e31b1b67300eb0a25' AND `scores`.`player_name` = '一') LIMIT 1):
   app/controllers/scores_controller.rb:59:in `create'

Any ideas?
Thank you.

HeChian Hsu
hechianhsu@gmail.com