Comment out the BASE_URL from your site.php and check out the configuration section.
If the relative directory (after BASE_URL) is different for your different locations, also comment out the DIR_REL definition, concrete5 will automatically detect the relative directory if it is not set.
After commenting out the BASE_URL option, your site will show up on any url that is pointed to your server's concrete5 installation. This is not usually the optimal case because for SEO purposes it is suggested to use EITHER www.site.com OR site.com. This can be fixed with the following configuration in your site.php:
Please note that if you do not have BASE_URL_POSSIBILITIES defined, this package will not do anything.