Jubler integrates with Google Translation for doing machine translations.
Navigate to the Tools menu, and click 'Translate'
The next screen you will see is the dialog box to select which caption to translate, and from what source language to what target language.
Here I will leave it at the default, 'By user selection', as my only caption is selected. Also, I make sure its English to French translation. Click 'OK', and if you are conneted to the internet, your translation should appear automatically. The French translation of my caption above is shown below.
There has been error in communication with Booktype server. Not sure right now where is the problem.
You should refresh this page.