Hot Link Protection

How can I protect Hot-Link?
Since i'm installed vBseo, this doesn't work:

Code:

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www\.)?skatsboard\.de(/.*)?$ [NC]
RewriteRule \.(gif|jpg)$ - [F]

This above was in a .htaccess File in the Folder "attachments" and work for me, but since Vbseo it doesn't.

Hello,

please try to add the same to the forums root .htaccess (at the top of other rewrite rules).