PAGINATION PROBLEM

http://www.snowboarditaliamag.it/mag/magazine (user: sim pass: simcity)
This is the page which is taking me crazy…

Please note that this page displays posts coming from 11 different subcategories of category parent category ‘mag’. They are extracted using this query:

<?php if (is_category('magazine')) { ?>
<h1>SNOWBOARD ITALIA MAGAZINE</h1><p>tutti gli articoli mag</p>
<?php query_posts('cat=28,38,39,43,44,45,60,69,77,78,85'); ?>  <!-- tira fuori le 8 categorie del menu MAG + update, prodotti-aziende, people-team -->
<?php } elseif (is_category('board-sport')) { ?>
<h1>ALTRI BOARD SPORT</h1><p>testo libero statico</p>
<?php global $query_string; query_posts($query_string); ?>
<?php } elseif (is_category('english')) { ?>
<h1>NEWS IN ENGLISH</h1><p>testo libero statico</p>
<?php global $query_string; query_posts($query_string); ?>
<?php } elseif (is_category('eventi-contest')) { ?>
<h1>EVENTI E CONTEST</h1><p>testo libero statico</p>
<?php global $query_string; query_posts($query_string); ?>
<?php } elseif (is_category('interviste')) { ?>
<?php } else { ?><?php } ?>

and pagination works with this:

<div class="pagination">

<?php if (function_exists("pagination")) {
    pagination($additional_loop->max_num_pages);
} ?>

 </div>

where function pagination is:

function pagination($pages = '10', $range = 3)
{
     $showitems = ($range * 2)+1; 

     global $paged;
     if(empty($paged)) $paged = 1;

     if($pages == '')
     {
         global $wp_query;
         $pages = $wp_query->max_num_pages;
         if(!$pages)
         {
             $pages = 1;
         }
     }  

     if(1 != $pages)
     {
         echo "<div class=\"pagination\"><span class=\"pagbg\">Pagina ".$paged." di ".$pages."</span>";
         if($paged > 2 && $paged > $range+1 && $showitems < $pages) echo "<a href='".get_pagenum_link(1)."'>&laquo;</a>";
         if($paged > 1 && $showitems < $pages) echo "<a href='".get_pagenum_link($paged - 1)."'>&lsaquo; Successivi</a>";

         for ($i=1; $i <= $pages; $i++)
         {
             if (1 != $pages &&( !($i >= $paged+$range+1 || $i <= $paged-$range-1) || $pages <= $showitems ))
             {
                 echo ($paged == $i)? "<span class=\"current\">".$i."</span>":"<a href='".get_pagenum_link($i)."' class=\"inactive\">".$i."</a>";
             }
         }

         if ($paged < $pages && $showitems < $pages) echo "<a href=\"".get_pagenum_link($paged + 1)."\">Precedenti &rsaquo;</a>";
         if ($paged < $pages-1 &&  $paged+$range-1 < $pages && $showitems < $pages) echo "<a href='".get_pagenum_link($pages)."'>&raquo;</a>";
         echo "</div>\n";
     }
}

which is working fine on the other pages….

Thanks!