[support] creating forums with drupal_execute

[Stefan Borchert]

Hi.
I'm trying to import forum data from fud to drupal.
Creating the containers is done very easy but if I want to create the 
forums within these containers it fails:
<code>
   $containers = _fud_get_categories();
   foreach ($containers as $data) {
     $values['name'] = utf8_encode($data->name);
     {...}
     // this works:
     drupal_execute('forum_form_container', $values);
     // get new tid from database...
     $tid = {...}
     $forums = _fud_get_forums($data->id);
     foreach ($forums as $forum) {
       $values['name'] = utf8_encode($forum->name);
       {...}
       $values['parent'][0] = array($tid => $tid);
       drupal_execute('forum_form_forum', $values);
     }
   }
</code>
The second drupal_execute runs into an error: "An illegal choice has 
been detected. ..." (form.inc: function _form_validate(); #555).
I know why this error appears but I don't know how to solve it: if you 
create a forum (admin/content/forum/add/forum) the list of parents is 
build by using taxonomy_get_tree().
After creating a forum container with drupal_execute the tree isn't 
updated (static variable in taxonomy_get_tree()) so the new container 
isn't available in the parent list and the "illegal choice" error is thrown.
Is there a way how to update the tree? Or clear the static variable 
(static $children) in taxonomy_get_tree()?
Or is it possible to set $form['#DANGEROUS_SKIP_CHECK'] with 
drupal_execute() (if set the options wont be checked)?
I tried but couldn't get it work.

(The other option is to create the containers first, create a mapping 
array (old id from fud => new tid in drupal) and then create the forums.
But this would be the last option.)

greetings,

  Stefan