Here is the official list of languages, keyboard layouts and dictionaries supported by the iPad (source link below):
Full language support for the following languages:
- Dutch
- English
- French
- German
- Italian
- Japanese
- Russian
- Simplified Chinese
- Spanish
Keyboard support for the following keyboard layouts:
- Dutch
- English (USA)
- English (United Kingdom)
- Flemish
- French (France and Canada)
- German
- Italian
- Japanese (QWERTY layout)
- Russian
- Simplified Chinese (Pinyin/Handwriting)
- Spanish
Dictionary support for the following languages:
- Dutch
- English (USA)
- English (United Kingdom)
- Flemish
- French
- French (Canadian variant)
- French (Swiss variant)
- German
- Italian
- Japanese
- Russian
- Simplified Chinese (Pinyin/Handwriting)
- Spanish
See Apple’s site for more details (link)