Can you just ssh into the box and run Thunderbird then? I do that at home all of the time. Sometimes it takes a while for Thunderbird to go through all of the messages, but since all of the heavy computing is being done on the server, it generally isn't too bad.
If you have to run it continuously then you might want to try 'xpra', which seems to be 'screen' for X11 apps. I've never tried it before and only found it when trying to see if screen works with X11 apps. I also have no idea if Mageia has it. http://xpra.org/ http://www.digipedia.pl/man/doc/view/xpra.1/
