just wondering if you are referring to configure inbound access to webserver (or email server) that is located in the pix inside net.
e.g.
www <--> pix <--> webserver (or email server)
if the above simplified topology is accurate, then it depends on the number of public ip.
for one public ip,
static (inside,outside) tcp interface 80 80 netmask 255.255.255.255
static (inside,outside) tcp interface 25 25 netmask 255.255.255.255
access-list inbound permit tcp any interface outside eq 80
access-list inbound permit tcp any interface outside eq 25
access-group inbound in interface outside
clear xlate
for multiple public ips,
static (inside,outside) netmask 255.255.255.255
static (inside,outside) netmask 255.255.255.255
access-list inbound permit tcp any eq 80
access-list inbound permit tcp any eq 25
access-group inbound in interface outside
clear xlate
