MU site / rewrite .htaccess

Hi,

My site is located here: http://www.brap.fm and I’m trying to using Pretty Permalinks on said site and remove the index.php portion of the URL.

I’ve installed the AskApache RewriteRules Viewer and apparently I’m not using using_mod_rewrite_permalinks. How do I get this enabled? Is this an .htaccess thing?

If so then could someone perhaps take a look at my .htaccess and tell me where I’m going wrong?

# BEGIN WordPress
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^([_0-9a-zA-Z-]+/)?files/(.+) wp-includes/ms-files.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule  ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule  ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]
# END WordPress