Bugzilla is developing rapidly, and has a strong developer and support community in its newsgroup and IRC channel.
Bugzilla also has comprehensive documentation.
Bugzilla is a server application, you must be using your Mac OS X box as a webserver to make use of it.
What's new in this version:
Optimized database structure for increased performance and scalability
Excellent security to protect confidentiality
Advanced query tool that can remember your searches Integrated email capabilities
Editable user profiles and comprehensive email preferences
Comprehensive permissions system