Dhcp Sever

How do I set up a DHCP sever on a Panadyne 6381 DSL modem?
I want to have 3 computers networked and sharing one internet connection, but there is a "IP address conflict". I tried changing the IP address is countless different ways, but none worked. I need to be able to either set it up to work with 3 IP addresses or as a DHCP server. Their website doesn't help because Panadyne has been bought by another company which messed up thier customer service.

You can buy a router and add it in between modem and other computers. Make sure the router has DHCP option available. I use a Dlink 524 from past 2 yrs. It is working pretty good.