how to configure 2 windows servers on a same LAN using 1 internet

hi, i like to know how to configure 2 windows 2003 servers using 2 dhcp on same lan connection, the lan connection is connected using a fiber-optic cable via a modem on each office and connected to the network switch.

both the servers are on same domain name.
both the servers is configured with ISA Server 2004,
both the servers is connected to wireless routers.

server 1 IP: 192.168.0.2
server 2 IP: 192.168.1.1

both the servers clients should be able to connect two servers,the internet connection is connected to server 1, i want the server 2 clients also to use server 1 for internet connection.

thanks,
ismail,