Here is CMS list of Free Software and Open Source.
Alfresco
http://en.wikipedia.org/wiki/Alfresco_%28software%29
Apache Lenya
http://en.wikipedia.org/wiki/Apache_Lenya
b2evolution
http://en.wikipedia.org/wiki/B2evolution
BBlog
http://en.wikipedia.org/wiki/BBlog
Mambo
http://en.wikipedia.org/wiki/Mambo_%28CMS%29
Moodle
http://en.wikipedia.org/wiki/Moodle
Joomla!
http://en.wikipedia.org/wiki/Joomla%21