Today, Google announced the integration of automatic translation of emails directly into the Gmail inbox. This integration takes the form of an option to be activated in the Labs.
To translate your messages just go activate “Message Translation” under setting tab
2009-05-20_195820 When you receive an e-mail in a language not your own, Gmail helps you to translate in a single click. The function adds a clickable link that will translate all the messages received in a different language to that used by default.
Check the new features for Google Mobile