http://www.phprojekt.com/index.php
That may work out for you.
"PHProjekt is a groupware suite which supports communication and management of teams and companies via Intranet and Internet. Components are: group calendar with resource booking, time card system, project management, request tracker, mail client, mutual filesystem, contact manager, mail client, forum, chat, notes, todo lists, voting system, reminder and more. An API allows the integration of available addons (e.g. web-shop, cms WAP suite a.o.) or own applications. Extensive help system, language files are available for 27 languages."