// <![CDATA[
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 (matchArray==null) 
{
	alert("Email address seems incorrect (check @ and .'s)")
	return false
}
var user=matchArray[1]
var domain=matchArray[2]

if (user.match(userPat)==null) 
{
    alert("The username 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 address is invalid!")
		return false
    }
  }
    return true
}

var domainArray=domain.match(domainPat)
if (domainArray==null) 
{
	alert("The domain name doesn't seem to be valid.")
    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) 
{
   alert("The address must end in a three-letter domain, or two letter country.")
   return false
}

if (len<2) 
{
   var errStr="This address is missing a hostname!"
   alert(errStr)
   return false
}

return true;
}
// ]]>