For / as with:
http://wiki.mydomain.com/index.php/Main_Page
php_flag register_globals off
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php?title=$1 [L,QSA]
--+
For /wiki as with:
http://www.mydomain.com/wiki/index.php/Main_Page
php_flag register_globals off
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /wiki/index.php?title=$1 [L,QSA]