The right statement is "issue tracking"
Mine's a development setup(personal).
- SVN because I started and am stuck with it
- Trac issue tracking and ticketing (with an XMLRPC plugin for auto ticketing & changelogging)
I think you can reuse some of the concepts. Also checkout JIRA and its various configuration options and supporting tools
Am sure there are better setups, Google has more answers than you would get here
tinm@n