Lightweight, minimalistic, viable CMS to learn Ruby On Rails?

What CMS would yo开发者_JAVA技巧u suggest to learn Ruby On Rails?

Some criteria:

1. It's minimalistic, lightweight but viable
2. Great software design
3. Good documentation
4. Active community
5. Internationalization

Thanks, Alpha Sisyphus

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I'd head to http://refinerycms.com/

This one is great too: http://www.locomotivecms.com/