exclude sticky post and categories in loop

Hello,
i’m trying to solve a problem in a templates i use as hompage in WP.

I’ve differents loops and i need one that:
1- excludes sticky post
2- excludes post from some categories

I found this:

<?php $sticky = get_option('sticky_posts') ;
$post_to_exclude[] = $sticky[0];

$args=array(
   'cat' =>-4,
   'caller_get_posts'=>1,
   'showposts'=>2,
   'post__not_in'=> $post_to_exclude,
);
query_posts($args); ?>

which excludes sticky posts and post from category 4.
But i can’t find a way to exclude another category (let’s say 4 AND 6).

I tryed many versions, for example

$args=array(
 'category_and' => array(-4,-6),
   'caller_get_posts'=>1,
   'showposts'=>2,
   'post__not_in'=> $post_to_exclude,
);

but the filter doesn’t filter, i mean, when i don’t get errors the filter pass all the post from all the categories.

Any idea?
Thanks a lot,
Molokom