=== modified file 'ahah_helper.module'
--- ahah_helper.module	2010-01-18 14:00:17 +0000
+++ ahah_helper.module	2010-01-18 14:54:13 +0000
@@ -110,6 +110,9 @@
     drupal_add_js(drupal_get_path('module', 'ahah_helper') . '/ahah_helper.js', 'footer');
     $js_file_added = TRUE;
   }
+
+  // Add our submit function, which will clean up form storage, so that redirects will work.
+  $form['#submit'] = array('ahah_helper_real_submit');
 }
 
 /**
@@ -121,6 +124,13 @@
 }
 
 /**
+ * Submit callback; gets rid of storage at the end, so that we can redirect.
+ */
+function ahah_helper_real_submit($form, &$form_state) {
+  unset($form_state['storage']);
+}
+
+/**
  * Given a POST of a Drupal form (with both a form_build_id set), this
  * function rebuilds the form and then only renders the given form item. If no
  * form item is given, the entire form is rendered.
@@ -139,6 +149,14 @@
   $form = form_get_cache($form_build_id, $form_state);
   $args = $form['#parameters'];
   $form_id = array_shift($args);
+
+  // Are we on the node form?
+  $node_form = FALSE;
+  if (preg_match('/_node_form$/', $form_id)) {
+    $node_form = TRUE;
+    module_load_include('inc', 'node', 'node.pages');
+  }
+
   // We will run some of the submit handlers so we need to disable redirecting.
   $form['#redirect'] = FALSE;
   // We need to process the form, prepare for that by setting a few internals
@@ -191,6 +209,14 @@
 
   // Build, validate and if possible, submit the form.
   drupal_process_form($form_id, $form, $form_state);
+  if ($node_form) {
+    // get the node from the submitted values
+    $node = node_form_submit_build_node($form, $form_state);
+
+    // hack to stop taxonomy from resetting when the form is rebuilt
+    $form_state['node']['taxonomy'] = taxonomy_preview_terms($node);
+  }
+
   // This call recreates the form relying solely on the form_state that the
   // drupal_process_form set up.
   //$form = drupal_rebuild_form($form_id, $form_state, $args, $form_build_id);