Can I use Gamespy Arcade to play games cross-platform from PC to Xbox 360?

I was browsing the internet and came across this website:

http://www.joystiq.com/2007/08/15/gamespy-tech-unreal-engine-3-crossplatform-ps3-and-pc-online/

I did some further research and found this:

http://www.maxconsole.net/?mode=news&newsid=19812

and

http://forums.maxconsole.net/showthread.php?t=74813

but I still can't find out how to make this feature work..

Can it be done and how?

Having done some research myself, it appears that the cross-platform multiplayer is limited to certain games that Microsoft want to make it open to.

Another thing is that Microsoft is only allowing these games to be cross-platformed for a limited time period.

Have a look at this link where they made Shadowrun cross-platformed for free last month (shame it's already run out)

http://www.1up.com/do/newsStory?cId=3169039

It also appears that "Universe at War: Earth Assault" and "Lost Planet: Colonies" were also other game titles that Microsoft have temporarily allowed.

So in a summary, it doesn't look like there's going to be much market with the PC to 360 link, but I imagine that Sony will open up seeing as their multiplayer facility is free.

No, most games have servers dedicated to one system or another, maybe microsoft has the odd game which because of its features can possibly cross-platform but it is unlikely due to the fact that they charge money to play on line