function equalHeight(group) {
  tallest = 0;
  group.each(function() {
    thisHeight = $(this).height();
    if(thisHeight > tallest) {
      tallest = thisHeight;
    }
  });
  group.height(tallest);
}

$(document).ready(function(){
  $('a.lightbox').lightBox({
    txtImage: '<?=$lang_const[js][lightbox][str1]?>',
    txtOf: '<?=$lang_const[js][lightbox][str2]?>'
  });
  
  equalHeight($(".cat-item-grp"));  						  
});