WordPress MU

I am running wpmu 2.6.5 using subdomains and installed on root level.

If I upload another web package, for example phpmyadmin, to the public_html folder (so its public_html/phpmyadmin/), it is accessable from all subdomains as well (i.e. http://subdomain.topdomain.com/phpmyadmin/).

Is there an easy .htaccess line anyone is aware of or other means such that these other programs are only available at top level domain (i.e. http://domain.com/phpmyadmin/) and not any of the subdomains?

Thanks,

I've spent some time digging through htaccess tutorials and am unable to determine the proper way to handle this.

Is this how you all have your site set up? i.e. if you upload another folder to you root folder, it is accessable from all subdomains as well?