Projectfork is an open source project management component for Joomla CMS. It is theme-able and can be extended by using extensions (free & paid). It has a built-in calendar control to help you define deadlines for tasks, milestones and projects.
Projectfork is a feature rich project management component, look at few of them:
- Adaptive layout
- Customizable panels for project info
- Create and archive infinite projects
- Milestones for groups of tasks
- Time tracker & file manager
- Access level control (ACL)
Nice and well featured.
For people looking for a simpler project management I can suggestion ProjectPier:
http://www.projectpier.org/
Or Ofuz
Open source download:
http://ofuz.com/opensource/
Online version:
http://ofuz.com/