Problem installing Domino 651 using Connectix Virtual PC

Very curious if anyone has good suggestions for me on this one:

I’m trying to install an additional Domino 651 server, using Connectix Virtual PC running Windows 2000 Server. My primary Domino 5.0.12 server is running on my Windows 2000 Professional host machine. To be more clear: both servers should run on the same physical hardware, but 651 has to run in a virtual environment.

When setting up the server configuration I keep getting the message “Server not responding. …”. I assume the fault is in where I have to enter the Other server and an Optional Network Address. I’ve tried entering both the server name and IP address, but no difference. I’ve modified hosts and lmhosts, even added entries to DNS, but no solution yet.

Both machines can ping each other and even nping (NotesConnect) confirms connection from my virtual environment to my primary Domino server (on port 1352). So at a low level all network connections seem to be available.

Any clues or directions where to look are greatly appreciated!