Domain Mapping sunrise and /wp-admin

Hi,
I just upgraded from WPMU 2.9.2 to WP 3.0.1 multisite and am installing the domain mapping plugin. Apparently, "//define( 'SUNRISE', 'on' );" is no longer included in the wp-config.php code. Does it matter where I add it?

I forwarded a domain (domain.org) to blog.mydomain.org. My domain host allows me to select URL Masking, Subdomain Forwarding and Path Forwarding. If I select them all the domain.org resolves to blog.mydomain.org. However, since blog.mydomain.org is hidden, domain.org/wp-admin does not work. The plugin's "Custom Domain Mapping" must be blank. If I add http://domain.org to Custom Domain Mapping, the browser keeps trying to load the webpage multiple times, repeating quickly. If I uninstall the plugin and use only the domain forward, it doesn't work.

If I try to use CNAME, the form appears to be asking for a subdomain on the domain.org name.

Any ideas?
Thanks,
Chuck S.