function checkEmail()
{
	var yourEmail = document.emailForm.yourEmail.value;
	var friendEmail = document.emailForm.friendEmail.value;
	if(yourEmail=="")
	{
		alert("Please enter your Email address");
		return false;
	}
	else if(friendEmail=="")
	{
		alert("Please enter your friend's Email address");
		return false;
	}
	if(verifyEmail(yourEmail)&&verifyEmail(friendEmail))
	{
		return true;
	}
	else
	{
		return false;
	}
}

function verifyEmail(emailStr)
{
	var checkTLD=1;
	var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
	var emailPat=/^(.+)@(.+)$/;
	var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	var validChars="\[^\\s" + specialChars + "\]";
	var quotedUser="(\"[^\"]*\")";
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom=validChars + '+';
	var word="(" + atom + "|" + quotedUser + ")";
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	var matchArray=emailStr.match(emailPat);

	if (matchArray==null) {
		alert("Email address "+emailStr+" seems incorrect (check @ and .'s)");
		return false;
	}
	var user=matchArray[1];
	var domain=matchArray[2];
	
	for (i=0; i<user.length; i++) {
	if (user.charCodeAt(i)>127) {
		alert("The username in  "+emailStr+" contains invalid characters.");
		return false;
   	}
	}
	for (i=0; i<domain.length; i++) {
	if (domain.charCodeAt(i)>127) {
		alert("Ths domain name in  "+emailStr+" contains invalid characters.");
		return false;
   }
  }

	if (user.match(userPat)==null) {
		alert("The username in  "+emailStr+" doesn't seem to be valid.");
		return false;
	}

	var IPArray=domain.match(ipDomainPat);
	if (IPArray!=null) {
		for (var i=1;i<=4;i++) {
		if (IPArray[i]>255) {
		alert("Destination IP in  "+emailStr+" is invalid!");
		return false;
   	}
}
return true;
}

var atomPat=new RegExp("^" + atom + "$");
var domArr=domain.split(".");
var len=domArr.length;
for (i=0;i<len;i++) {
if (domArr[i].search(atomPat)==-1) {
alert("The domain name in  "+emailStr+" does not seem to be valid.");
return false;
   }
}

if (checkTLD && domArr[domArr.length-1].length!=2 &&
domArr[domArr.length-1].search(knownDomsPat)==-1) {
alert( emailStr+"  must end in a well-known domain or two letter " + "country.");
return false;
}

if (len<2) {
alert( emailStr+"  is missing a hostname!");
return false;
}

return true;
}