Query posts by custom fields, conditional query

Hello

what am I trying to do is query all posts containing the same custom fields, but only if they satisfy ALL custom fields in the query..

example:

the normal query :

<?php query_posts('meta_key=color&meta_value=black
&meta_key=shape&meta_value=circle&orderby=title&order=asc');  ?>

  <?php while (have_posts()) : the_post(); ?>

 <a href="<?php the_permalink() ?>"><?php the_title(); ?></a>&nbsp;,&nbsp;

  <?php
   global $wp_query;
   $postid = $wp_query->post->ID;
   echo get_post_meta($postid, 'color', true);
  ?>

  <?php endwhile;?>

with this query i got all the posts containing the custom field value “black” OR “circle” but I want to display the post link just in case it has got exactly the two values, and not only one.

How should the code look for that?

Thank you