Mod rewrite rule problem

[gecko1]

I know this is a frequently asked question, but I just can't seem to get this to work.

I want to redirect my site from www.domain.com to just [domain.com...]

My .htaccess file already has:

RewriteCond %{REQUEST_FILENAME}!-f

RewriteCond %{REQUEST_FILENAME}!-d

RewriteRule ^(.*) index.php

which I need for SEF advance that I am running. Can someone please help explain what I need to change?

[gecko1]

I am adding this to the file:

RewriteCond %{http_host} ^www\.domain\.jp [nc]
RewriteRule ^(.*)$ [domain.jp...] [r=301,nc]

[gecko1]

I got this working now, with the above code.