Domino 7.0.2 FP1 intermittent slow response on x64

I have customer with a Windows 2003 R2 x64 server running Domino 7.0.2 FP1.

The server is an IBM x3550 wth 2GB RAM and a 2.13GHz Dual Core Xeon CPU, running a dedicated Domino server for 3 users.

They use the server for their private mailboxes as well as two shared application mailboxes (about 300MB, approx. 20000 documents each).

When paging thorugh the document view, the server will appear to hang for 5-10 seconds on every 15-20th move in the view with the little lightning on.

I have the very same mail database application running on a much older (and slower) x230 type server with Windows 2003 32bit, also with 2GB RAM with the same type of application mailboxes (size >2GB with 200000 documents in each) for 10 users - and the thing just flies.

I know that Domino currently is a 32bit application, but does this explain the poor response times on Windows 2003 x64 ?

Any help would be appreciated,

Alex Rasmussen