//-------------------------------------------
// TO CALL:
// on any email field on a form add - 
//
// onblur="javascript:emailCheck(this.value);"
//
//--------------------------------------------


function emailCheck (emailStr) {
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(emailStr != "")
{
	if (matchArray==null) {
		alert("Please enter a valid email address.");
		return false;
	}
	var user=matchArray[1];
	var domain=matchArray[2];
	
	// See if "user" is valid 
	if (user.match(userPat)==null) {
		// user is not valid
		alert("Please enter a valid email address.");
		return false;
	}
	
	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("Please enter a valid email address.");
			return false;
			}
		}
		return true;
	}
	
	// Domain is symbolic name
	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
		alert("Please enter a valid email address.")
		return false
	}
	
	var atomPat=new RegExp(atom,"g");
	var domArr=domain.match(atomPat);
	var len=domArr.length;
	if (domArr[domArr.length-1].length<2 || 
		domArr[domArr.length-1].length>3) {
	   // the address must end in a two letter or three letter word.
	   alert("Please enter a valid email address.");
	   return false;
	}
	
	// Make sure there's a host name preceding the domain.
	if (len<2) {
	   var errStr="Please enter a valid email address.";
	   alert(errStr);
	   return false;
	}
}
// If we've gotten this far, everything's valid!
return true;
}
//  End -->