function validateZIP(field,field2,field3,field4) {
  
  var valid = "0123456789-";
  var hyphencount = 0;
  var errmsg="";
  var flg="T";
  if(field4.length!=0){
      if(field4 =="42" || field4=="52" || field4=="62" || field4=="72" || field4=="9995"){
      }
      else{
        errmsg=errmsg+ "\nThis Promotion Code is not valid.";
        flg="F";
      }
  }
  if(field2==false && field3==false){
     errmsg=errmsg+"\nSelect Residential or Enterprise.";
     flg="F";
  }
  
  
  if (field.length!=5 && field.length!=10) {
    errmsg=errmsg+ "\nEnter your 5 digit zip code.";
    flg="F";
  }
 for (var i=0; i < field.length; i++) {
    temp = "" + field.substring(i, i+1);
    if (temp == "-") hyphencount++;
    if (valid.indexOf(temp) == "-1") {
       errmsg=errmsg+ "\nInvalid characters in your zip code.  Please try again.";
       flg="F";
    }
    if ((hyphencount > 1) || ((field.length==10) && ""+field.charAt(5)!="-")) {
      errmsg=errmsg+ "The hyphen character should be used with a properly formatted 5 digit+four zip code, like '12345-6789'.   Please try again.";
      flg="F";
   }
 }
 if(flg=="F"){
   alert(errmsg);
   return false;
 }
return true;
}