uri mod_rewrite to remove index.php

[eluser]nuttynibbles[/eluser]
location of .htaccess file: /home/example/public_html/
location of codeigniter files: /home/example/public_html/codeigniter/

url: http://example.com/codeigniter/index.php/blog/yahoo
the above link will call class blog and function yahoo and echo some text.

i have research other threads on ways to remove index.php by mod_rewrite but stil not successful.

here is the conent of my .htaccess:
Options -indexes
DirectoryIndex index.php
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /codeigniter/index.php/$1/ [L]

tks..