RE: Sametime Meetings and 64-bit Windows 7 Markku M Hanninen 21.Jan.14 04:07 AM a Web browser Online Meeting Center/Meeting Room 8.5.2 IFR1Windows
Sametime community server is 32-bit only, so you need to use 32-bit domino server on your new 64-bit hardware. This isn't problem as 32-bit domino/sametime works fine in Windows 64-bit environment.
When it comes to your java problem, if the problem is that with newer version it doesn't find java and says its unavailable, there is fix to it. I had the same problem.
The problem is that the script that does the java check does it by checking it from windows registry clsid. In the newer versions of java, the clsid changed and the script doesn't work(script does very poor job of detecting java). I debugged the script and found the error, then notified IBM via PMR and they provided me with fixed script later on. So if that is your problem, open PMR and get a new script.
I haven't tested with 64-bit browser but i think it should work fine as well as the meeting room uses java. Generally, 64-bit browser isn't that necessary anyways, Windows has both 32-bit and 64-bit versions of Internet Explorer installed and most other browsers work in 32-bit as the 64-bit doesn't really help browsers much anyway.