Documentation for JIRA 4.4. Documentation for other versions of JIRA is available too.
JIRA can be easily integrated with many popular source control systems:
The most scalable and recommended solution is to use FishEye, which supports Subversion, Git, Perforce, Clearcase, CVS, and Mercurial with real-time notifications of code changes plus web-based reporting, visualisation, search and code sharing.