I just read an article on lifehacker.com about Translation in Google Talk. It works very good. Only the last translation should have been "Do you speak Dutch?", very strange the translation was actually a change in language even in the text.
This feature from Google could really help me since English isn't my mother language. You can just invite the bot to your Google Talk account. Use language codes. For example Dutch to English is done by the bot email@example.com and English to French is done by firstname.lastname@example.org.