Db:migrate do not run correctly

Hi,

When i run this command i have an error :

rake db:migrate --trace
rake aborted!
NoMethodError: undefined method `ord’ for 0:Fixnum: SET NAMES ‘utf8’

see the log in attached file.
my database.yml file is here :


MySQL. Versions 4.1 and 5.0 are recommended.

development:
adapter: mysql
encoding: utf8
reconnect: false
database: annuaire_development
pool: 5
username: root
password:
host: 127.0.0.1

test:
adapter: mysql
encoding: utf8
reconnect: false
database: annuaire_test
pool: 5
username: root
password:
host: 127.0.0.1

production:
adapter: mysql
encoding: utf8
reconnect: false
database: annuaire_production
pool: 5
username: root
password:
host: 127.0.0.1


Thanks

My config :

WampServer 2.0 with MySQL 5.0.51a
Aptana 2.0.4
Ruby 1.8.5
Gems:
actionmailer (2.3.4, 2.3.2)
actionpack (2.3.4, 2.3.2)
activerecord (2.3.4, 2.3.2)
activeresource (2.3.4, 2.3.2)
activesupport (2.3.4, 2.3.2)
cgi_multipart_eof_fix (2.5.0)
fastthread (1.0.1)
gem_plugin (0.2.3)
linecache (0.43)
mongrel (1.1.5)
mysql (2.8.1, 2.7.3)
rack (1.0.0)
rails (2.3.4, 2.3.2)
rake (0.8.7)
ruby-debug-base (0.10.3)
ruby-debug-ide (0.4.5)
sqlite3-ruby (1.2.1)