کد:
RewriteEngine On
Options +Followsymlinks
RewriteBase /
RewriteCond %{HTTP_HOST} .
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteCond %{HTTP_HOST}<>%{REQUEST_URI} ^([^.]+)\.domain\.com?<>/([^/]*) [NC]
RewriteCond %1<>%3 !^(.*)<>\1$ [NC]
RewriteRule   ^(.*)$ - [E=SUBDOMAIN:%1]

RewriteCond %{ENV:SUBDOMAIN} ^(.+)$
RewriteRule ([^/]+)^$ index.php?w=%1$1 [L]