How to refresh a modal dialog

[JohnRock]

Using Web Flow, I have a modal pop up form that gets displayed when the user clicks on the link below:

<a id="addPMTpopup" href="${flowExecutionUrl}&_eventId=addPayment">Add Payment</a>

                    <script type="text/javascript">
                        Spring.addDecoration(new Spring.AjaxEventDecoration({
                            elementId: "addPMTpopup",
                            event: "onclick",
                            popup: true,
                            params: {fragments: "newpayment"}
                        }));
                    </script>

How can I refresh this modal popup? For example if a Validator fails? Whenever I try to reload the view it is no longer a modal popup, but a brand new view. How can I refresh the popup without losing the view it is on top of?

Specifically, what I want to do is call a transition that updates the model and then redraws the modal popup with the updated mapped model data.