Thanks for your reply,
This means that i can buy two licences, install one as gateway on the server and the 2nd one can be installed on the three laptops to join the VPN server. Am i correct?
Please also inform me about Mac based machine support.
With VPN you need the number of licenses which would cover the number of joiners - so if you have one VPN server and only one joiner which connectes two networks together you need two users. You do not need licenses for every computer behind Wingate.
You are correct - provided you do not run other license-consuming services, like proxy, mail, etc.
As of MAC support - Wingate itself runs on Windows systems only, but from the client side Macs will work just fine as well as other IP-based networking systems. I run MacOS X, Solaris, PocketPC, Linux and FreeBSD behind Wingate VPN, for one.