function CardNumber1_AutoTab(cc1, cc2) {
	var ctl = document.getElementById(cc1);
	if (ctl.value.length == 4) { 
		ctl = document.getElementById(cc2);
		ctl.focus();
	}
}

function CardNumber2_AutoTab(cc2,cc3) {
	var ctl = document.getElementById(cc2);
	if (ctl.value.length == 4) { 
		ctl = document.getElementById(cc3);
		ctl.focus();
	}
}

function CardNumber3_AutoTab(cc3,cc4) {
	var ctl = document.getElementById(cc3);
	if (ctl.value.length == 4) { 
		ctl = document.getElementById(cc4);
		ctl.focus();
	}
}

function CardNumber4_AutoTab(cc4,ccv) {
	var ctl = document.getElementById(cc4);
	if (ctl.value.length == 4) { 
		ctl = document.getElementById(ccv);
		ctl.focus();
	}
}