oTasks is a multi-user tasks management system, featuring a recursive and distributed task tree, an open user management system (everybody can create an account), and email notifications. It can be used as trouble-ticket system.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
Displaying subtasks and the "task path" (from root to current job) on task display screen, date support (start/deadline), fixes for some issues on the contact screen, and a new feedback form.