Due to some issues with Akamai caching, i want my site to be publicly available by 2 diffenent URLs.

The difference needs to be in the subdomain level,
eg:
Live site for public access should be: http://www.mysite.com
whereas the url for logged in users (admins) should be: http://admin.mysite.com

Live site is cached by Akamai so i need to make sure that admins use only admin.mysite.com in order to update it - no user access / cookies through the live one.

The thing is, i've installed the whole drupal installation on the live web server in a subdirectory called /drupal and i need to remove this from the urls.

.htaccess is all well configured both in / (root) and /drupal folders, but then i need to edit settings.php and set the $base_url.

Then, having 2 different subdomains is causing me the headache.

What should i do in this situation? Should i just create two different folders in /sites/all and give them different settings.php files?
Could that do the job, or is there any other easier way?

Can someone give me some advice?

Thanks in advance ;-)