Order posts by Category

Hi!
I want to show the posts ordered by Categorys AND date it means

Category 3
Post1 Date: 11/2008
Post2 Date: 04/2008
Post3 Date: 04/2008
Post4 Date: 03/2008

Category 1
Post1 Date: 10/2008
Post2 Date: 08/2008
Post3 Date: 04/2008

Category 2
Post1 Date: 09/2008
Post2 Date: 05/2008

It should receive the newest posts and show the category of newest post at Top.

I’m trying it with
query_posts(array('order'=>'ASC'.'&orderby=category'));
but it doesn’t work ??

has anyone some idea how to solve it?

thanks ??