CakePHP .htaccess mod_rewrite configuration to exclude a particular folder/url

Hi

I have a CakePHP installation in a sub folder in my server, I want to install another application inside that subfolder:

root/public_html/subfolder/cake/
root/public_html/subfolder/app/

etc. now I need a custom application installed there:

root/public_html/subfolder/my_custom_application/

I have something like this in my .htaccess:


   RewriteEngine on
   RewriteRule    ^$ app/webroot/    [L]
   RewriteRule    (.*) app/webroot/$1 [L]

How can I configure it to exclude the "my_custom_application" folder from that rules?

I tried this:


   RewriteEngine on
   RewriteRule    ^$ app/webroot/    [L]
   RewriteRule    ((?!my_custom_application).*) app/webroot/$1 [L]

But I get this:

Error:  The requested address '/y_custom_application' was not found on this server.

Thanks in advance.

Mauricio.