var ShipAddress1 = "";
var ShipAddress2 = "";
var ShipCity = "";
var ShipZip = "";

function InitSaveVariables(form) {
ShipAddress1 = form.ShipAddress1.value;
ShipAddress2 = form.ShipAddress2.value;
ShipCity = form.ShipCity.value;
ShipZip = form.ShipZip.value;
}

function ShipToBillPerson(form) {
if (form.copy.checked) {
InitSaveVariables(form);
form.ShipAddress1.value = form.Address1.value;
form.ShipAddress2.value = form.Address2.value;
form.ShipCity.value = form.City.value;
form.ShipZip.value = form.Zip.value;
}
else {
form.ShipAddress1.value = ShipAddress1;
form.ShipAddress2.value = ShipAddress2;
form.ShipCity.value = ShipCity;
form.ShipZip.value = ShipZip;       
   }
}