function emailCheck (formname, textboxname, displaytext) 
{
	err= emailCheck1 (formname, textboxname, displaytext);
	if (err !="")
	{
		if (document.getElementById)
	       document.getElementById('emailfield').innerHTML="<font color='red'><strong>Email: </strong></fornt>";
	}
	else
	{
		if (document.getElementById)
	       document.getElementById('emailfield').innerHTML="Email: ";
	}
	 
	return err;
}
	
function emailCheck1 (formname, textboxname, displaytext) {
var emailStr;
  emailStr=eval('document.'+formname+'.'+textboxname+'.value');
var err;
var checkTLD=1;
var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum|COM|NET|ORG|EDU)$/;
var emailPat=/^(.+)@(.+)$/;
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) {


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

// See if "user" is valid 
if (user.match(userPat)==null) {
 err=  "- The username doesn't seem to be valid.<br>\n";
 return err;
}

var IPArray=domain.match(ipDomainPat);
if (IPArray!=null) {

for (var i=1;i<=4;i++) {
if (IPArray[i]>255) {
err=  "- Destination IP address is invalid!<br>\n";
return err;
   }
}
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) {
   err= "- The domain name does not seem to be valid.<br>\n";
   return err;
    }
  }
if (checkTLD && domArr[domArr.length-1].length!=2 && 
  domArr[domArr.length-1].search(knownDomsPat)==-1) {
   err= "- The address must end in a well-known domain or two letter " + "country.<br>\n";
  return err;
 } 

if (len<2) {
  err=  "- This address is missing a hostname!<br>\n";
  return err;
 }
 err="";
 return err;
}