function changemenu(obj, what){
  jmeno =  $(obj).attr("alt"); 
  if(what == 1){
      $(obj).attr("src", "/wp-content/themes/twentyten/images/" + jmeno + "_.png");
  }
  else {
      $(obj).attr("src", "/wp-content/themes/twentyten/images/" + jmeno + ".png");
  }  
}