function openWindow(path, windowName) {
	if (windowName==undefined) {
		windowName = 'popUp';
	}
	win = window.open(path,windowName,'location=1,toolbar=1,directories=1,status=1,menubar=1,scrollbars=1,resizable=1');
	win.focus();
	return false;
}

/* Checks that the credit card number is valid */
function checkNumber(theNumber) {
	var digits = new Array();
	for (var n=0; n< theNumber.length; n++) {
		digits[n] = theNumber.charAt(n) - 0;
	}

	var sum = 0;
	var alt = false;
	for(var i = digits.length - 1; i >= 0; i--) {
		if(alt) {
			digits[i] *= 2;
			if(digits[i] > 9) digits[i] -= 9; 
		}
		sum += digits[i];
		alt = !alt;
   }
   return sum % 10 == 0;
}