Here is mine:
ErrorDocument 404
http://www.all.com
ErrorDocument 403
http://www.all.com
ErrorDocument 500
http://www.all.com
SetEnvIf Referer .xxxsex\.com refer
SetEnvIf Referer .all\.com refer1
SetEnvIf Referer .xamocontent\.com refer2
Deny from all
Allow from env=refer
Allow from env=refer1
Allow from env=refer2
I use this to use a global members area for several sites, works perfectly.
You *may* need to contact you host about a special string to go at the top - without this partcilar string, mine doesn`t work- but it won`t necessarily be the string for you-
Options +FollowSymlinks
-