[CentOS] layer 8 / user level firewall on linux?

Hi all,

Does anyone know of a Linux firewall that offers layer 8 firewall /
user level firewalling? Cyberoam
(http://www.cyberoam.com/firewall.html) has a layer 8 firewall built
into their UTM firewalls, and while it's a great product I find it a
bit limited for what I want.

I basically want to track which user access what on the internet, from
an internal network. Ideally I want to limit access to certain objects
(i.e. websites, by URL / keyword / type, FTP, skype, MSN, etc) for
certain users as well.



-- 
Kind Regards
Rudi Ahlers
CEO, SoftDux Hosting
Web: http://www.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532