version = navigator.appVersion.toLowerCase();
agent = navigator.userAgent.toLowerCase();
ie = (version.indexOf('msie')>-1);
ie50 = (version.indexOf('msie 5.0')>-1);
win = (version.indexOf('windows')>-1);
opera = (agent.indexOf('opera')>-1);

function display (elementID)
{
var id;

if ((ie) &! (opera)) {

      id = "area" + elementID;
      document.all.item(id).style.display = "block";
   }
else {

      id = "area" + elementID;
      document.getElementById(id).style.display = "block";
   }
}
function undisplay (elementID)
{
var id;

if ((ie) &! (opera)) {
     id = "area" + elementID;
      document.all.item(id).style.display = "none";
   }
else {
     id = "area" + elementID;
      document.getElementById(id).style.display = "none";
   }
}

function check_post_addr()
{
  var chb = document.getElementById('post_addr_checkbox');
  var post_box = document.getElementById('post_addr_box');
  if (chb.checked) {
    post_box.style.display = "block";
  }
  else {
    post_box.style.display = "none";
  }
}



function pozn_zv (io)
{
  var elem;
  var Elem = io + "_pozn";
	if(document.getElementById) {
		var elem = document.getElementById(Elem);
	} else if (document.all){
		var elem = document.all[Elem];
	}
	if (elem.className=="pozn")
	{
    elem.className = "poznzv";
  }
  else
  {
    elem.className = "pozn";
  }
	
/*
  var id = io + "_pozn";
  if (action=="1")
  {
    .style.class = "poznzv";  
  }
  else
  {
    document.getElementById(id).style.class = "poznzv";  
  }
*/  
}



function changeClass(Elem, myClass) {
	var elem;
	if(document.getElementById) {
		var elem = document.getElementById(Elem);
	} else if (document.all){
		var elem = document.all[Elem];
	}
	elem.className = myClass;
}