i18n server-side vs. client-side

Seeking some advice on two approaches to internationalization & localization. I have a web app using Spring MVC and Dojo, and I would like to support multiple languages. So, I could:

1. Use <spring:message> to generate the appropriate text on the server side using a properties file.
2. Use dojo/i18n to select the appropriate text on the client side using a js file.

And of course any combination of the two is also an option.

So, what are the pros and cons of each approach? When would you use one vs. the other?