Situation:
I'm running the ultravnc server 1.0.1 + mirrordriver as service on a WinXP box.
The client is running on another WinXP box.
Both are using the DSM plugin MSRC4Plugin_NoReg.dsm V1.1.8.
They're connected through a 500kbit/s line, so I'm using the "medium" preset.
This works just fine

The problem:
Sometimes (about 1 or 2 times per week), the viewer suddenly closes itself. This might even happen while its minimized (I'm not entirely sure though).
When I reconnect, I get the "WriteExact: DSMPlugin-RestoreBuffer Alloc Error", right after entering the password.
The next (usually two) login attempts result in a "Unknown VNC authentication result!".
Then it starts over again with the WriteExact error.
Sometimes the viewer opens after a login attempt (instead of displaying the WriteExact error), but closes itself right after the initial screen refresh.
The problem eventually fixes itself after some time. However it usually takes about one hour (hmm, screensaver on the server?), and I'm basically locked out during that time.
It doesn't seem to be connection related, since low-traffic datastreams continue to flow normally in the moment the viewer closes itself.
Server & client were rebooted at some time, yet the problem occurred again somewhen. So its not a one-time thing.
Any idea yet?
If not: Do I need to start both the server & the client in debug mode, or can I keep running the server as service, as only the client logs might be of relevance?