Webmail subdomain problems

Hi... firstly I will thank you for your time in responding to my query, I know it is a pretty nub question

I have a new server with Ubuntu 9.10 64bit "Pefect Server ISPConfig 3", which I decided to be game and use one of your VMWare images

I made the neccessary modifications, ran all updates etc.. mostly everything is working, I just have one issue with RoundCube webmail

I have roundcube installed in /usr/local/roundcube

I have added "/usr/local/roundcube" to the PHP open_basedir settings in ISPConfig -> System -> Server Config -> Web

I have created /etc/apache2/conf.d/roundcube.conf:

Code:

Alias /webmail /usr/local/roundcube

<Directory "/usr/local/roundcube">
Options Indexes FollowSymlinks
AllowOverride None
Order allow,deny
Allow from all
AddDefaultCharset off
</Directory>

I can access "http://virtual.server.com/webmail" and it works
I can set a "subdomain" webmail.virtual.server.com with a redirect to "http://virtual.server.com/webmail" and it takes me to the webmail page

I don't want the full address "http://virtual.server.com/webmail" to display in the address bar though, I just want "http://webmail.virtual.server.com" to display

I have tried a redirect to "/webmail/" but it doesn't seem to work
I get this error in the apache logs
File does not exist: /var/www/virtual.server.com/web/webmail

How do I make my redirect to "http://virtual.server.com/webmail" work without showing the full address in the bar? I just want it to show "http://webmail.virtual.server.com"

I don't want to have to create any symlinks (as this cannot be done within the control panel)