function ValidateEmail(emailStr)
{			
	if (emailStr.length == 0)
    {
        alert("The email is required.");
        return false;
    }			
	
	if (!emailCheck (emailStr))
    {
        alert("The email is not valid.");
        return false;
    }	
	
	var emailPat=/^(.+)@(.+)$/;
	var matchArray=emailStr.match(emailPat);
	var domain=matchArray[2];
	
	var knownFreeDomains=/^(gmail.com|hotmail.com|yahoo.com|yahoo.de)$/;
	
	if (domain.search(knownFreeDomains) != -1)
		return confirm("It will take 5 days to verify free email address. Do you want to change your email address to a different one or continue?")				
	else
		return true;			
}

function ValidateEmailNoPopup(emailStr)
{		
    var returnString = "";
    	
	if (emailStr.length == 0)
    {
        returnString = "Need to enter an email address"
    }			
	
	if (!emailCheck (emailStr))
    {
        returnString = "Email must be of the form username@domain.ext with no spaces"
    }	
	
	return returnString
}

function emailCheck (emailStr) 
{
	/* 	The following variable tells the rest of the function whether or not
		to verify that the address ends in a two-letter country or well-known
		TLD.  1 means check it, 0 means don't. */
	var checkTLD=1;
	
	/* The following is the list of known TLDs that an e-mail address must end with. */
	var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum|au|de)$/;
	
	/* 	The following pattern is used to check if the entered e-mail address
		fits the user@domain format.  It also is used to separate the username
		from the domain. */
	var emailPat=/^(.+)@(.+)$/;
	
	/* 	The following string represents the pattern for matching all special
		characters.  We don't want to allow special characters in the address. 
		These characters include ( ) < > @ , ; : \ " . [ ] */
	var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	
	/* 	The following string represents the range of characters allowed in a 
		username or domainname.  It really states which chars aren't allowed.*/
	var validChars="\[^\\s" + specialChars + "\]";
	
	/* 	The following pattern applies if the "user" is a quoted string (in
		which case, there are no rules about which characters are allowed
		and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
		is a legal e-mail address. */
	var quotedUser="(\"[^\"]*\")";
	
	/* 	The following pattern applies for domains that are IP addresses,
		rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
		e-mail address. NOTE: The square brackets are required. */
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	
	/* 	The following string represents an atom (basically a series of non-special characters.) */
	var atom=validChars + '+';
	
	/* 	The following string represents one word in the typical username.
		For example, in john.doe@somewhere.com, john and doe are words.
		Basically, a word is either an atom or quoted string. */
	var word="(" + atom + "|" + quotedUser + ")";
	
	// 	The following pattern describes the structure of the user
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	
	/* 	The following pattern describes the structure of a normal symbolic
		domain, as opposed to ipDomainPat, shown above. */
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	
	/* 	Finally, let's start trying to figure out if the supplied address is valid. */
	/* 	Begin with the coarse pattern to simply break up user@domain into
		different pieces that are easy to analyze. */
	var matchArray=emailStr.match(emailPat);
	
	if (matchArray==null) {
		/* 	Too many/few @'s or something; basically, this address doesn't
			even fit the general mould of a valid e-mail address. */
		//alert("Email address seems incorrect (check @ and .'s)");
		return false;
	}
	
	var user=matchArray[1];
	var domain=matchArray[2];
	
	// 	Start by checking that only basic ASCII characters are in the strings (0-127).
	for (i=0; i<user.length; i++) {
		if (user.charCodeAt(i)>127) {
			//alert("Ths username contains invalid characters.");
			return false;
   		}
	}
	
	for (i=0; i<domain.length; i++) {
		if (domain.charCodeAt(i)>127) {
			//alert("Ths domain name contains invalid characters.");
			return false;
   		}
	}
	
	// See if "user" is valid 
	if (user.match(userPat)==null) {
		// user is not valid
		//alert("The username doesn't seem to be valid.");
		return false;
	}
	
	/* 	if the e-mail address is at an IP address (as opposed to a symbolic
		host name) make sure the IP address is valid. */
	var IPArray=domain.match(ipDomainPat);
	if (IPArray!=null) {
		// 	this is an IP address
		for (var i=1;i<=4;i++) {
			if (IPArray[i]>255) {
				//alert("Destination IP address is invalid!");
				return false;
   			}
		}
		return true;
	}

	// Domain is symbolic name.  Check if it's valid.
 
	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 does not seem to be valid.");
			return false;
   		}
	}

	/* 	domain name seems valid, but now make sure that it ends in a
		known top-level domain (like com, edu, gov) or a two-letter word,
		representing country (uk, nl), and that there's a hostname preceding 
		the domain or country. */
	if (checkTLD && domArr[domArr.length-1].length!=2 && 
		domArr[domArr.length-1].search(knownDomsPat)==-1) {
		//alert("The address must end in a well-known domain or two letter " + "country.");
		return false;
	}
	// Make sure there's a host name preceding the domain.
	if (len<2) {
		//alert("This address is missing a hostname!");
		return false;
	}
	// If we've gotten this far, everything's valid!
	return true;
}