JQuery :: Confirmation Dialog Inside Ajax Form Not Waiting

I have a form on a page that allows users to enter/edit and delete calendar events. The form is handled with Alsup's .ajaxForm plug-in [URL]. I would like to add a delete confirmation to the functionality in the form of a "Are you sure?" dialog box. Regardless of whether I open the confirmation in the "beforeSubmit" callback or a separate button.click function, the problem is the same: the "beforeSubmit" callback isn't waiting for the confirmation dialog to close.

Here's what I have so far:
var fr_confirm = false;
var d_confirm = $( "#dialog-confirm" ).dialog({
autoOpen: false
,closeOnEscape: false
,resizable: false
,modal: true
,buttons: {
"Delete content": function() {
fr_confirm = true;
$( this ).dialog( "close" );},
Cancel: function() {
$( this ).dialog( "close" );
}}});
$('#form_review').ajaxForm({
url: './includes/save_event.php'

,beforeSubmit: function(formData, jqForm, options) {
// grab the text of the button selected - the last item in the data array
var b = formData[formData.length-1].value;
if ("Delete" == b) {
d_confirm.dialog('open');
if (fr_confirm) {
fr_action.val('delete');
var rid = fr_edit_rev.val();
} else {
return false;
}} else if ("Reset" == b) {
Form_Review_Reset();
return false;
} else { // submit
// form data validation
...
}}
,success: function(json, statusText, xhr, $form) { // post-submit callback
...
}});

The first-to-mind hackish idea of
while (d_confirm.dialog( "isOpen" )) {}
Only causes the browser to hang. And setTimeout would also fall thru without waiting for the response. And I ~really~ don't want to use the old alert() function, even tho that is precisely the functionality I want to mimic.