Friendly url's MAMP OS X

I just did a fresh install of modx 1.0.2, the latest GA version. For some reason the friendly url’s aren’t working and I get a Not Found
The requested URL /index.php was not found on this server whenever I click a link. I think I did everything I’m supposed to do, like
rename the htaccess file.

For the record I am using the latest version Mamp on leopard. Am I the only one experiencing problems with this setup?
This is my first install btw... So I might have missed some things.

It works when I manually add "http://localhost/modx/" to this line in the .htaccess. Is that how I should go about this in the future?

RewriteRule ^(.*)$ http://localhost/modx/index.php?q=$1 [L,QSA]

A simple yes or no will do

Do you have :

in your .htaccess file?