Hello,

So far I've been using postfix only to enable php mail() function. What I need to do is a mail system web interface for give to some of my users.

I have 3 websites and I'd like to make the mail on these urls to hand out to users of each:

mail.domain1.com
mail.domain2.com
mail.domain3.com

Is it possible with Citadel?
Could you please guide me what's the best solution in this case? I'm using Ubuntu 10.04. I'm new to this, so some "spoon feeding" guide is much appreciated

You can switch to Citadel, but you'll have to remove Postfix and install/configure Citadel in its place since it's an integrated system*.

Alternatively, you could keep Postfix and install an add-on webmail package like Squirrelmail or Roundcube.

Unfortunately I don't have any particular how-to documents to recommend, but a search will turn up many for each option.

*It might be possible to set it up alongside Postfix, but that's not the normal configuration.