Basically, this little tutorial explains how to make it so when a visitor goes to a site on your domain through http://webmail.(ANY_SITE).com
, they will be presented with a single install
webmail package. I didn't want to use ISPConfig's package, nor did I want to have my users all log in to mydomain.com:81/webmail. This method allows you to create one site, and have all your clients use their own page to get their webmail.
Follow a tutorial to install a webmail package to your domain. I recommend RoundCube: http://www.howtoforge.com/roundcube_webmail_ispconfig
Once you have this installed and have verified that RoundCube works, move on to the next step.
Log in as root to your server
Choose an editor of your choice and edit: /etc/httpd/conf/httpd.conf
Scroll down to the bottom and add BEFORE the "Include /etc/httpd/conf/vhosts/Vhosts_ispconfig.conf"
DirectoryIndex index.html index.php
AddType application/x-httpd-php .php .php3 .php4 .php5
Be sure to change the specified fields.
Give it a minute or two and now when a user visits:
They will all be presented with one webmail package that you installed in the beginning.
Also (contributed by roadster). You will have to add in a new co-domain (Check the DNS box too) for each site you want this to work on, simply add the following to your co-domains area: