Antivirus for windows 2003 R2 64 bit

Hi,

I am using windows 2003 R2 64 bit trial version for evaluation purpose on a desktop machine, if we are able to deploy our application (ASP.net 2.0 based web application) and there is a significant boost of performance than we’ll use it.

One issue we are facing is no antivirus is working on windows 2003 R2 64 bit , and I don’t have a budget to support antivirus server purchase during evaluation time (i.e. less then two months) , Could anybody tell me some free / trial antivirus which work with windows 2003 R2 64 bit . I dont need an antivirus server , all I need a product to make one desktop running windows 2003 R2 64 bit secure .

Thanks a lot,

Samant

PS: I tried to locate a forum for windows 2003 R2 64 bit but could not find one, apologies to post it in vista forum