function hasOptions(obj){if(obj!=null && obj.options!=null){return true;}return false;}

function copySelectedOptions(from,to){
	var options = new Object();
	if(hasOptions(to)){
		for(var i=0;i<to.options.length;i++){
			options[to.options[i].value] = to.options[i].text;
		}
	}
	for(var i=0;i<from.options.length;i++){
		var o = from.options[i];
		if(o.selected){
			if(options[o.value] == null || options[o.value] == "undefined" || options[o.value]!=o.text){
				var index=to.options.length;
				to.options[index] = new Option( o.text, o.value, false, false);
				from.options[i] = null;				
			}
		}
	}

}


function oznac_vse(to){
  for (var i=0; i<to.options.length; i++) {
    to.options[i].selected = true;
  }
}