Web based email client capable of setting different domain

[Reuben D. Budiardja]

Hi all,
I hope someone can help me and/or show me if there's easier solution for this.

I have a mail forwarding set up so that any email sent to 
user at forwarding-domain.com goes to my own mail server (running sendmail, 
stock RHEL 3 install). 

I wondering if there's a web based solution that I can run on my mail server, 
so that any email that was sent from the web-based mail client looks like it 
comes from forwarding-domain.com. 

I know that most modern mail client can do this "forging From / Reply-to" 
address (ie. Kmail, Evolution, don't know anything about Win mail client) by 
setting up different "Identity". But we are planning to do this for about 15 
people and I just want to provide a 'standard' solution for everyone.  

I'm not ready yet to set up our own mail server with its own domain name, so I 
thought this email forwarding feature that we got when we bought the domain 
name is the simplest way to go, at least for now. Oh, please be assured I'm 
not trying to spam anyone :)

Thanks for any help / info on this.
RDB
-- 
Reuben D. Budiardja
Department of Physics and Astronomy
The University of Tennessee, Knoxville, TN
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