free help desk solution

[Jonathan Hernández Velasco]

Hi, I have an Ubuntu (hoary) and i'm searching for a free help desk
application. The serverside would be linux-based (for the hoary) and the
client-side would be web-based (multiplatform).

I have some examples of "help desk application" (final links), but most
of them are based in "tickets" or only for windows (and all propietary),
i'm more interested in live contact (chat, transfer files easily... i
have an vncserver (realvnc) instaled in all pcs, so remote connection
would be easy).

Some example links of commercial help desk applications:

http://www.auscomp.com/intranet_helpdesk_google.html
http://www.netretina.com/
http://helpdesk-software.ws
http://www.wonderdesk.com/
http://www.perldesk.com/

So... someone knows a free "help-desk" solution with some of this
features? :-) Any help would be appreciated, thanks in advance!

-- 
Jonathan Hernández Velasco aka jBilbo 
http://jhernandez.gpltarragona.org
Vpte. GPLtarragona ;; http://www.gpltarragona.org
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