function head_17_change(i){
	if (document.getElementById(i).style.backgroundPosition == "0px -17px") {
		document.getElementById(i).style.backgroundPosition = "0px 0px";
	} else {
		document.getElementById(i).style.backgroundPosition = "0px -17px";
	}
}

function set_true(i){
	document.getElementById(i).value = "true";
}

function set_checkbox(i){
	if (document.getElementById(i).value !== "true") {
		document.getElementById(i).value = "true";
	} else {
		document.getElementById(i).value = "false";
	}
}

function mehrzeilen(){
	var f = 1;
	while (f <= 10) {
		if (document.getElementById("adress_zusatz_"+f).style.display == "none"){
			document.getElementById("adress_zusatz_"+f).style.display = "";
			break;
		}
		f++;
		if (f==10){
			document.getElementById("mehrzeilen").style.display = "none";
		}
	}
}

function set_checkbox_newbg(i, f){
	set_checkbox(i);
	if (document.getElementById(f).style.backgroundImage == "url(../img/misc/checkbox_2.gif)"){
		document.getElementById(f).style.backgroundImage = "url(../img/misc/checkbox_1.gif)";
	} else {
		document.getElementById(f).style.backgroundImage = "url(../img/misc/checkbox_2.gif)";
	}
}

function submit_over(a){
	document.getElementById(a).style.backgroundPosition = "0px -21px";
}
function submit_out(a){
	document.getElementById(a).style.backgroundPosition = "0px 0px";
}

function formcheck(){
	if (document.getElementById('4_anrede').value == "" ||
		document.getElementById('4_vorname').value == "" ||
		document.getElementById('4_nachname').value == "" ||
		document.getElementById('4_firma1').value == "" ||
		document.getElementById('4_land').value == "" ||
		document.getElementById('4_str').value == "" ||
		document.getElementById('4_plz').value == "" ||
		document.getElementById('4_ort').value == "" ||
		document.getElementById('4_tel').value == "" ||
		document.getElementById('4_email').value == "" )
	{
		alert('Mit einem Stern(*) gekennzeichnete Felder müssen ausgefüllt werden');
		return false;
	} else {
		return true;
	}
}