[LARTC] transparently passing url requests to local servers sharing ip?

[Skwerl]

hey, i'm hoping there's someone out there that can help me out...
i found http://lartc.org/howto/index.html through a friend who was 
trying to help with something i'm trying to accomplish.

for various practical and educational reasons, i have a few servers set 
up on my home network, all running apache on various operating systems, 
all accessible through port forwarding. i only have one ip which they 
all share. for instance:

http://24.30.102.177:1721/ is an osx server on the network 
(192.168.0.104)
http://24.30.102.177:1722/ is a slackware linux server on the network 
(192.168.0.101)
http://24.30.102.177:1723/ is a windows nt server on the network 
(192.168.0.106)

what i want to do is have something running on the linux box (which the 
router would dmz) that would take a url requested and let a particular 
server on the network serve a web site. i'd like it to be transparent 
to the client, so they never see port numbers in their address bar, and 
i'd like the web serving to be done by the box the files rest on; not 
strictly the linux box's apache.

i don't need someone to hold my hand through the whole process which i 
expect to be tricky, but i'd like to know if what i'm trying to do is 
even possible with linux routing- if i'm barking up the right tree so 
to speak. also, i don't seem to have iproute installed and every site 
which is supposed to have it seems to be down. do you know where i can 
get it? if i need it, that is.

i've been searching for a clue for some time now, and any light on this 
subject would be hugely appreciated!
skwerl