function EmailCheck (emailStr) {
	var emailPat=/^(.+)@(.+)$/
	var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
	var validChars="\[^\\s" + specialChars + "\]"
	var firstChars=validChars
	var quotedUser="(\"[^\"]*\")"
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
	var atom="(" + firstChars + 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) {
		return false
	}

	var user=matchArray[1]
	var domain=matchArray[2]

	if (user.match(userPat)==null) {
	    return false
	}

	var IPArray=domain.match(ipDomainPat)
	if (IPArray!=null) {
	  for (var i=1;i<=4;i++) {
		    if (IPArray[i]>255) return false;
		}
		
	  return true;
	}

	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
	    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>4) {
	   return false;
	}

	if (domArr[domArr.length-1].length == 1 && len<3) {
	   return false;
	}

	if (domArr[domArr.length-1].length==3 && len<2) {
		return false;
	}

	return true;
}