Subdomains Hosting Continuation

["Ivan Zanev" <ivan.ivanov.zanev@xxxxxxxxx>]

Well, thanks for the replies, you all! Here's what i did: I've create a sdsymlinks folder with symbolic links to the users subdomains. The htaccess is using the symlink, but here is what happens in several cases:

Let Superman has the x subdomain at thehost.com. That is: x.thehost.com

We access x.thehost.com: Everything works fine and index.html opens.

We access x.thehost.com/images: The images folder does not exist. Instead of displaying the Not Found error, we end up with recursion of urls. (will explain later).

We access x.thehost.com/images: The images folder exists. A list of files is displayed with the "Up One Level" link. We click on the Up on Level link. Instead of going into x.thehost.com (as it is the parent of x.thehost.com/images), we end up in x.thehost.com/files/sdsymlinks/x. Now let me walk you through my .htaccess file:

<IfModule rewrite_module>
    RewriteEngine On

    RewriteCond %{REQUEST_URI} ^/$
    RewriteCond %{HTTP_HOST} !^((cp\.)|(www\.)|(admin\.))
    RewriteCond %{HTTP_HOST} ^([^\.]+)\.besthost-bg\.com$
    RewriteRule (.*) files/sdsymlinks/%1/index.html [QSA,L]

    RewriteCond %{REQUEST_URI} !^/$
    RewriteCond %{REQUEST_URI} !files/sdsymlinks/
    RewriteCond %{HTTP_HOST} !^((cp\.)|(www\.)|(admin\.))
    RewriteCond %{HTTP_HOST} ^([^\.]+)\.besthost-bg\.com$
    RewriteRule (.*) files/sdsymlinks/%1/$1 [QSA,L]

    RewriteCond %{SCRIPT_FILENAME} !-f
    RewriteCond %{SCRIPT_FILENAME} !-d
    RewriteRule (.*) index.php?url="" [QSA,L]
</IfModule>

The first pair of conditions check if we are trying to access x.thehost.com (the REQUEST_URI is '/'). If this is the case, we will open index.html. 
The second pair of conditions check if we are trying to access x.thehost.com/something (the REQUEST_URI is not '/'). We also check if the REQUEST_URI matches files/sdsymlinks/. Now, why would I want to do that? The answer is, if I remove this
condition, we end up with recursion.  files/sdsymlinks/x is rewritten to files/sdsymlinks/x/files/sdsymlinks/x/ and so on, until the recursion is internally stopped from apache.
The third pair works if the subdomain is cp or www or admin in which cases we don't want to go to the files/sdsymlinks.

The problem is: I don't feel it right, because for every automatic operation, I must take care myself => not found, forbidden and so on. I've seen some hosting sites, where you can have a subdomain, no problem and everything works fine. But I can't get it right. Please help me!