htaccess and multiple applications

[eluser]trice22[/eluser]
I'm afraid I'll have to ask for some help again—I got stuck with my 404 after all.

If I remove the .htaccess both:

Code:

http://localhost:8888/ci_test/backend_index.php

and

Code:

http://localhost:8888/ci_test/frontend_index.php

works just fine.
But with the .htaccess (see above) only the frontend-part works, every controller in the backend returns a 404 and I'm starting to think I might still have a problem with the .htaccess.

I've tried:

Code:

RewriteEngine on

RewriteRule ^cms$ backend_index.php [L]
RewriteRule ^cms/(.*)$ backend_index.php/$1 [L]

RewriteCond $1 !^(frontend_index\.php|assets)
RewriteRule ^(.*)$ /ci_test/frontend_index.php/$1 [L]

and

Code:

RewriteEngine on

RewriteRule ^cms$ /ci_test/backend_index.php [L]
RewriteRule ^cms/(.*)$ /ci_test/backend_index.php/$1 [L]

RewriteCond $1 !^(frontend_index\.php|assets)
RewriteRule ^(.*)$ /ci_test/frontend_index.php/$1 [L]

Every help would be very appreciated.
Thanks,
—trice