Subdomains with .htaccess rewrite rules not working

Hey, i have a little problem.. i set a subdomain well:

subdomain.domain.ltd

it's work fine, but the problem is when i put an .htaccess file inside with a rewrite rule, for example:

RewriteEngine on

makes this:

domain.tld/path_to_subdomain -> Works well!

subdomain.domain.tld -> .htaccess error!!

Here was my config (added by ISPConfig):
/etc/httpd/conf/sites-available/domain.ltd.vhost

Code:

    RewriteEngine on
    RewriteCond %{HTTP_HOST}   ^subdomain.domain.ltd [NC]
    RewriteRule   ^/(.*)$ /var/www/clients/client0/web2/web/path_to_subdomain/$1  [L]

/var/www/clients/client0/web2/web/path_to_subdomain/.htaccess

Code:

RewriteEngine on
RewriteRule ^(.*)$ index.php [QSA,L]

domain.tld/path_to_subdomain -> Works well!

subdomain.domain.tld -> .htaccess error!!

it's very rare, i don't know what to do.. i tried lot of things

 

mmmm

here is my ugly solution:

Code:

    RewriteEngine on
    RewriteCond %{HTTP_HOST}   ^subdomain.domain.ltd [NC]
RewriteRule   ^/(.*)$ /var/www/clients/client0/web2/web/path_to_subdomain/index.php/$1  [L]

Adding the index.php works fine