Button Submit Disable

<!-- **************************** Checkbox **************************************** -->
<HTML>
<HEAD>
</HEAD>
<BODY>
<form enctype="multipart/form-data" action="#" method="post">

<input type="checkbox" name="Datenschutz" value="Ja" onmousedown="releasing(this)" />
<input type="submit" id="status" name="status" value="Bestellung abschicken" disabled />

</form>
</BODY>

<SCRIPT LANGUAGE="JavaScript">
function releasing(chk) {
var btn = document.getElementById('status');
if (chk.checked){
btn.disabled = true;
}
else {
btn.disabled =false;
}
}
</script>
</HTML>

<!-- **************************** Textbox **************************************** -->
<HTML>
<HEAD>
</HEAD>
<BODY>
<form enctype="multipart/form-data" action="#" method="post">

<input type="Text" id="txt" onmousedown="releasing2(this)" onkeyup="releasing2(this)" />
<input type="submit" id="status2" name="status" value="Feedback abschicken" disabled />

</form>
</BODY>
<SCRIPT LANGUAGE="JavaScript">
function releasing2(txt) {
var btn = document.getElementById('status2');
if (txt.value != '') {
btn.disabled = false;
}
else {
btn.disabled = true;
}
}
</script>
</HTML>