function getIndex(input) {
	var index = -1, i = 0, found = false;
	while (i < input.form.length && index == -1) {
		if (input.form[i] == input)index = i;
		else i++;
	}
	return index;
}
function autoTab(input,len, e) {
	if(input.value.length >= len) {
		input.value = input.value.slice(0, len);
		input.form[(getIndex(input)+1) % input.form.length].focus();
	}
}

function SelectCCType(ccform) {
	var frm = document.getElementById(ccform);
	if( frm== null) {
		frm = document.all[ccform];
	}

	if (frm.cc_type) {
		if 
		(
			frm.card_number1.value != ''
			|| frm.card_number2.value != ''
			|| frm.card_number3.value != ''
			|| frm.card_number4.value != ''
		) {
			frm.cc_type[1].checked=true;
		} else {
			frm.cc_type[0].checked=true;
		}
	}
}