What if domain doesn't use www

I have a domain name for example mydomain.com
The domain in listed in google without the www and it must stay there without it.

We created a subdomain called mydomain.com/mob/

I'm testing with the component to redirect iphone users to that domain and i only get errors.

is there a way to let this work (maybe a hack in the scirpts?)

mydomain.com/mob/ is not a subdomain, subdomain would be mob.mydomain.com

I know. i have a special menu for mobile users. this is a special layout that i can set with a menu item. For mobile devices i create a menu for a special component and there i set the layout. the data displaed is the same it's only the layout. for mobile users all URL's are mydomain.com/mob When a desktop user lands on mydoamin.com/category1 the mobile user normaly must land on mydomain.com/mob/category1 I now also tested with mobile.mydomain.com and the redirection works great. i anly need to set /mob/ after the mobile.mydomain.com any ideas? I think the script doesn't work with a /subfolder after the domainname.

Who can help me.When I set mij mobile page to: mobile.mydomain.com/mob the scripts gets errors. i need to set /mod and the of the domain,

Found it i used htaccess
RewriteCond %{HTTP_HOST} !^mobile.mydomain.com$ [NC]
RewriteCond %{HTTP_USER_AGENT} "android|blackberry|googlebot-mobile|iemobile|ipad|iphone|ipod|opera mobile|palmos|webos" [NC]
RewriteRule ^(.*)$ http : / / mobile.mydomain.com/mob/$1 [L,R=302]