RewriteEngine On
RewriteCond %{HTTP_HOST} ^(.+).www.uwsc.wisc.edu
RewriteCond %{DOCUMENT_ROOT}/%1/%{REQUEST_URI} -f [OR]
RewriteCond %{DOCUMENT_ROOT}/%1/%{REQUEST_URI} -l [OR]
RewriteCond %{DOCUMENT_ROOT}/%1/%{REQUEST_URI} -d
RewriteRule ^(.*)$ http://www.uwsc.wisc.edu/%1/$1 [P]