515E sharing 1 IP with multiple servers inside firewall

Hi there ,

I have the PIX 515E i have only 1 public IP address and I want to
share it with multiple server inside my private network. For example I
have 2 server 1 web at 192.168.1.10  and 1 mail server  at
192.168.1.20. I wish to have people who connect on my public IP  using
port 80 to forward to  my web server at 192.168.1.10 on port 80 and
people who connect on my public IP using port 110 to forward to my
mail server at 192.168.1.20. How can this done in the PIX ?



thanks

c1