redirect sub domain to a different machine

Hi,
I was wondering how can you setup apache - http.conf - to redirect a specific sub domain to a different machine (mirror). I was hoping to find a way to do that with as Virtual host and perhaps mount the disks from the other server to the live one. Or just send the requests directly to the other machine..

please advice,

http://httpd.apache.org/docs/1.3/mod/mod_alias.html

Redirecting from the Apache didn't really work out in my case. I had to mount the folder on the live server and setup the mounted file system as the sub domain.. here is what I did exactly

http://forums.kwtlinux.com/viewtopic.php?f=2&t=11

I bookmarked that page. Someone will ask again for sure.