ZdMultilang is a Multilingual plugin for WordPress allowing you to blog in more than one language. You can define multiple languages and translate posts/tags/categories using the interface that will be added to your blog’s administration panel.

This plugin is giving you the power to translate your blog, and doesn’t leave this job to tools such as Google translator or such. This is not an automatic translation plugin.

It’s compatible with WordPress 2.5 and 2.5.1.

Full documentation is available here in english and here in french.

And finally, you can grab the plugin here.