Ich weiß nicht, welche besonderen Anforderungen an ein CRM-System gestellt werden, deshalb mag folgender Hinweis etwas unpassend sein - aber vielleicht auch nicht... ;)
http://www.phpgroupware.org/ phpGroupWare (formerly known as webdistro) is a multi-user groupware suite written in PHP.
It provides a Web-based calendar, todo-list, addressbook, email, news headlines, and a file manager. The calendar supports repeating events. The email system supports inline graphics and file attachments.
The system as a whole supports user preferences, themes, user permissions, multi-language support, an advanced API, and user groups.
