Does Sonar support multiple language in same project?

If you are using Sonar version 3.4. Then I have written a new maven plugin to help you with multiple language code analysis.

It is still beta

https://code.google.com/p/sonar-multilang-maven-plugin/wiki/UserGuide

If you have any issues with this tool then do let me know on that project website.

UPDATE April 14th, 2014:

Starting with SonarQube 4.2, multi-language projects are supported.

This automatically happens when sonar.language is not set.

See my sample project here: https://github.com/bellingard/multi-language-project