<!-- Bilder vorladen -->
var preloadFlag = false;
function PreloadImages() {
if (document.images) {
  bild01 = new Image("/en/fotos/gmarkt_gr.jpg");
  bild02 = new Image("/en/fotos/HOTEL_GR.JPG");
  preloadFlag = true;
  }
}

<!-- Bildwechsel  -->
function imgwechsel(img_name,img_src) {
	if (document.images)
	document[img_name].src=img_src;
	document[img_name+"alt"].src=img_src;
}

function hinundher(objectID, clssName) {
	var divs = document.getElementsByTagName('span');
	for (var n = 0; n < divs.length; n ++) {
		if (divs[n].className != clssName) continue;
		divs[n].style.display = "none";
	}
	document.getElementById(objectID).style.display = "block";
	return false;	
}

<!-- Infofenster Datei-Upload -->
function FensterOeffnen (Adresse) {
  MeinFenster = window.open(Adresse, "Zweitfenster", "width=550,height=450,scrollbars=yes");
  MeinFenster.focus();
}
<!-- Infofenster Anfahrt -->
function FensterOeffnenAnfahrt (Adresse) {
  AdressFenster = window.open(Adresse, "Adressfenster", "width=705,height=760,resizeable=yes,scrollbars=yes");
  AdressFenster.focus();
}

function checkCheckBox(f){
if (f.agree.checked == false )
{
alert('Please confirm the indications through ticking the check-box. Then you can send your message. Thank you very much!');
return false;
}else
return true;
}