var IE4 = (document.all && !document.getElementById) ? true : false;
var NS4 = (document.layers) ? true : false;
var IE5 = (document.all && document.getElementById) ? true : false;
var NS6 = (document.getElementById && !document.all) ? true : false;

var reEmail = /^[a-zA-Z0-9_][\w\.-]*[\w]\@[\w\.-]+\.(com|edu|org|net|gov|mil|info|biz|name|cc|us|uk|ws|bz|tv|co|ca|de|jp|ro|tc|dk|gs|sh|be|st|vu|kz|lt|fm|ac|nz|to|ms|as|ph|vg){1}(\.(\w{2}))?$/;
var reZip = /^[0-9]{5}((\-)|(-[0-9]{4})|([0-9]{4}))?$/;
var reAreaCode = /^[0-9]{3}$/;
var rePrefix = /^[0-9]{3}$/;
var rePhone = /^[0-9]{4}$/;
var reDate = /^(([1]{1}[0-2]{1})|([1-9]{1})|([0]{1}[1-9]{1})){1}\/(([1-2]{1}[0-9]{1})|([3]{1}[0-1]{1})|([1-9]{1})|([0]{1}[1-9]{1})){1}\/((19[0-9]{1}[0-9]{1})|(20[0]{1}[0-9]{1})){1}$/;
var reInteger = /^[0-9]+$/;
var reExtension = /^[0-9]{1,5}$/;