Rewrite all 404s

[techieanalyst]

Im running IPBoards 3.4.2 and I need this problem solved and they've already pretty much pointed at the webserver

<IfModule mod_rewrite.c>
Options -MultiViews
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule \.(jpeg|jpg|gif|png)$ /public/404.php [NC,L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

All sites come back as 404, what should I set on my listener/server side in the GUI to make this work