I know its VPN but how?

I have a NT 4 PDC server behind a firewall in Singapore, i have 2 workstations (NTworkstation, Win2k Pro) in Hong Kong would like to log on to the domain in singapore every working day. what are the procedures i should do?

my thinking:
1) get aleased line in Hongkong
2) setup RAS in NT 4 Server
but how do i make the the workstations in Hongkong able to find this doamin in singapore during setup and subsequent log on?