dotProject is a PHP web-based project management framework that includes modules
for companies, projects, tasks (with Gantt charts), forums, files, calendar,
contacts, tickets/helpdesk, multi-language support, user/module permissions and 
themes.

Features Include

    * User Management
    * LDAP / Active Directory authentication
    * Email based trouble Ticket System, (Integrated voxel.net's ticketsmith)
    * Client/Company Management
    * Project listings
    * Hierarchical Task List
    * File Repository
    * Contact List
    * Calendar
    * Discussion Forum
    * Resource Based Permissions 

WWW: http://www.dotproject.net