Vine server 4.01 on OS X 10.8 server

I’m setting up a new Mac Mini that has OS X 10.8 Server Mountain Lion installed. I want to use the System Server from Vine Server on a non-standard port as this has always worked for me in the past. My VNC client is RealVNC Viewer.

I’ve downloaded the latest version of Vine server (4.01) and set up the system server. I can connect using the VNC client once a user has logged into the Mac Mini. If the Mac Mini has to be restarted, the VNC client shows the local authentication screen followed by the Mac Mini log in screen with a flashing cursor. However if I try to type the user’s password, the cursor freezes and no keystrokes are accepted. If I then log in directly on the Mac Mini, the VNC client is disconnected. I can then restart the VNC client and connect successfully.

Logging in on a Mac via Vine Server (system server) has worked previously on older versions of OS X Server and Vine server. What do I need to do to get this working on 10.8 Server?

This sounds to me like the same issue as discussed in this thread: