Last night after erasing my .htaccess file I lost some important mod-rewrite info. Being desperate I searched through this forum and found the solution which made me happy. Therefor I want to say thank u Richardk, also thx for all other answers you posted in this forum.
In my honest opinion something like the the following code should be added as a sticky as it seems to be the basic redirect for subdomain handling.
RewriteEngine On
RewriteCond %{HTTP_HOST} !^(www\.)?DOMAIN$ [NC]
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteCond %{HTTP_HOST} ^([^.]+)\.DOMAIN$ [NC]
RewriteRule .* /SUBDIR/PAGE?SOMETHING=%1 [L]
Once again, thx richardk. I enjoy the way you explain things and help others out.