function changeCheckbox(obj,checkboxname,imgfolder)
	{
		if(obj.innerHTML=="")
		{
			obj.innerHTML='<input type="hidden" name="'+checkboxname+'" value="1">';
			obj.style.backgroundImage="url("+imgfolder+"radio_button_active.gif)";
		}else{
			obj.innerHTML="";
			obj.style.backgroundImage="url("+imgfolder+"radio_button.gif)";
		}
	}