// version of navigator
	function verze()
		{
		appname = navigator.appName;
		appversion = navigator.appVersion;
		majorver = appversion.substring(0,1);
		if ( (appname == "Netscape") && (majorver >= 4 ) ) return 1;
		if ( (appname == "Microsoft Internet Explorer") && (majorver >= 4) ) return 1;
		return 0;
		}

		
// validates form	
	function ValidatePost(formular)	{
		if (verze()) {
			if (formular.jmeno_prijmeni.value=="") {
				alert("Jméno a příjmení musíte vyplnit!");
				formular.jmeno_prijmeni.focus();
				return false;
			} else {
				return true;
			}
		} else {
			return true;
		}
	}

	
// opens new window
function OpenWindow(PAGE) 
	{
		window.open(PAGE);
	}