function isEmailAddress (string) {
		var addressPattern = /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
		return addressPattern.test(string);
	}

	function notEmptyStr(strValue) {
		var objRegExp  = /[^ \t\v\f\n\r]$/;
		return objRegExp.test(strValue);
	}
	
	function isPhoneNumber(strValue) {
		var cleanPhone = strValue.replace(/\D/g, "")
		var tenDigits  = /\d{10}/;
		return tenDigits.test(cleanPhone);
	}		
	
	function checkSubmitOrder() {
		var error='';
		if (notEmptyStr(document.getElementById('orderForm').fName.value)==false) {
			error+='Please enter your first name.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').lName.value)==false) {
			error+='Please enter your last name.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').mAddress.value)==false) {
			error+='Please enter your mailing address.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').mCity.value)==false) {
			error+='Please enter your mailing city.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').mState.value)==false) {
			error+='Please enter your mailing state.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').mZip.value)==false) {
			error+='Please enter your mailing zip code.\r\n';
		}		
		if (isPhoneNumber(document.getElementById('orderForm').phone.value)==false) {
			error+='Please enter your full ten-digit phone number.\r\n';
		}	
		if ((document.getElementById('orderForm').ccVisa.checked==false) && (document.getElementById('orderForm').ccMC.checked==false) && (document.getElementById('orderForm').ccAmex.checked==false)) {
			error+='Please select your credit card type.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').ccNum.value)==false) {
			error+='Please enter your credit card number.\r\n';
		}
		if (notEmptyStr(document.getElementById('orderForm').ccExpiration.value)==false) {
			error+='Please enter your credit card expiration date.\r\n';
		}
		if (error=='') {
			return true;
		} else {
			alert (error);
			return false;			
		}
	}
	
	function checkSubmitSubscribe() {
		var error='';
		if (notEmptyStr(document.getElementById('subscribeForm').fName.value)==false) {
			error+='Please enter your first name.\r\n';
		}
		if (notEmptyStr(document.getElementById('subscribeForm').lName.value)==false) {
			error+='Please enter your last name.\r\n';
		}
		if (notEmptyStr(document.getElementById('subscribeForm').mAddress.value)==false) {
			error+='Please enter your mailing address.\r\n';
		}
		if (isPhoneNumber(document.getElementById('subscribeForm').phone.value)==false) {
			error+='Please enter your full ten-digit phone number.\r\n';
		}	
		if ((document.getElementById('subscribeForm').subType.checked==false) && (document.getElementById('subscribeForm').subType.checked==false)) {
			error+='Please designate your subscription as new or a renewal.\r\n';
		}
		if (document.getElementById('subscribeForm').series.value=="0") {
			error+='Please select the series for which you wish to subscribe.\r\n';
		}		
		if ((document.getElementById('subscribeForm').ccVisa.checked==false) && (document.getElementById('subscribeForm').ccMC.checked==false) && (document.getElementById('subscribeForm').ccAmex.checked==false)) {
			error+='Please select your credit card type.\r\n';
		}
		if (notEmptyStr(document.getElementById('subscribeForm').ccNum.value)==false) {
			error+='Please enter your credit card number.\r\n';
		}
		if (notEmptyStr(document.getElementById('subscribeForm').ccExpiration.value)==false) {
			error+='Please enter your credit card expiration date.\r\n';
		}
		if (error=='') {
			return true;
		} else {
			alert (error);
			return false;			
		}
	}