on the detail page, find the following:
<?php
// WA eCart Redirect
if ($WA_Store_Cart->redirStr != "") {
header("Location: ".$WA_Store_Cart->redirStr);
}
?>
and change it to:
<?php
// WA eCart Redirect
if ($WA_Store_Cart->redirStr != "") {
session_commit();
header("Location: ".$WA_Store_Cart->redirStr);
}
?>