Anti Hotlinking for use with multiple domains (e.g. HTTP HOST)

Multi Domain Anti Hotlinkging, htaccess, mod rewrite

[celebx]

Hi!

I was wondering if anyone knows a solution to be able to install hotlinking on a site wich uses multiple (10000+) domains.

Maybe this is possible using something like:

rewriteEngine On

rewriteCond %{HTTP_REFERER}!^$
RewriteCond %{HTTP_REFERER}!%{HTTP_HOST}
RewriteRule (.*) /images/alert.gif [R,NC,L]

But this doesn't seem to work...

Please help!

Best Regards,
Snt