Screen Sharing hangs after a few minutes idle

I've enabled Screen Sharing on my Mac and am connecting from a Windows machine. I've tried connecting with TigerVNC, TightVNC, and TurboVNC clients but after about 10 minutes of no activity on the screen hangs. I'm able to move the mouse pointer, but no screen updates are sent over to the client. Reconnecting works, but it's a nuisance to have to connect every ten minutes 🙂

Any help on how to debug this would be appreciated. I bought my machine a month ago and I have the latest updates installed. Both the Mac and the VNC client are on the same LAN switch.

Thanks.

- Amir