How to setup virtual hosts

[B. Buehler]

Hi

I haven't been successful in searching a guide to setup a virtual host yet. 

I would like to type instead of   "www.mykolab.ch"    "mail.mykolab.ch"   in 
the browser and I would like the horde client to open directly from that link.

It's clear that extern, a suitable DNS-entry is necessary.

Is there anywhere such a guide, so that I as a Non-Apache-Guru can come along 
with that?

If not, I would be very grateful for an example about it.

Thanks a lot.

Bernhard