Here's how I set it up on my Mac running 10.6, and our Mac Server (10.6 too).
- Run Server Admin on your local machine
- Open up the server you want to connect to
- Select Firewall.
- Go to Settings / Services tab
- If 'Allow traffic only to these ports' is selected we need to add the ports that VNC will use.
- Click the little + button at the bottom-left of the list of services
- Add a new service called VNC 1, using port 5800, TCP + UDP
- Add a second service, VNC 2, using port 5900, TCP + UDP
- Stop and restart the firewall
- Download Chicken of the VNC and install it.
- Run the app
- Go to Connection / New Connection
- Enter the IP address or name of your server
- Leave 'display' as 0 (if you choose 1 you'd have needed to open ports 5801/5901 above for example)
- Leave 'profile' as 'default profile'
- Check the 'save server' box.
- Hit connect.
If all goes well you should have a window pop up displaying the screen of the server.