function email_validation(form){
	 
var emailStr=form.email.value
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)")
	 form.email.focus();
	return (false)
}
var user=matchArray[1]
var domain=matchArray[2]
if (user.match(userPat)==null) {
    alert("The username doesn't seem to be valid.")
	 form.email.focus();
    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("Destination IP address is invalid!")
			 form.email.focus();
		return (false)
	    }
    }
    return (true)
}
var domainArray=domain.match(domainPat)
if (domainArray==null) {
	alert("The domain name doesn't seem to be valid.")
	 form.email.focus();
    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.")
    form.email.focus();
   return (false)
}
if (len<2) {
   var errStr="This address is missing a hostname!"
   alert(errStr)
   form.email.focus();
   return (false)
}



}