.htaccess question

I developed an html mobile site for a client who's main site is php. The problem is when I try to access m.clientssite (the subdomain I created) I get a page not found. I called Hostgator and they said I need to turn off the rewrite engine in htaccess to be able to view it. I did and then I could view it.... however, the main site links did not work... I got page not found. So, I turned rewrite back on so the main site worked, but now, no mobile! I called Hostgator again and got a different tech who said there was no way around the problem... that it was a catch 22.

So, before I give up, I thought I'd take advantage of you genius people here to see if I can maybe add something in the htaccess file that will fix it. Here is what is currently in the file..



RewriteEngine on
RewriteBase /
RewriteRule ^(.*)\.html$ $1.php [L]

AddType text/html .shtml
AddHandler server-parsed .html
AddHandler server-parsed .shtml
Options Indexes FollowSymLinks Includes



My client uses this php site as the master site to over 50 others that are affiliates so he can update them all at once. Thanks for any help!