#default_value=>NULL in profile edit

I'm testing Drupal 6.1, PostgreSQL 8.3 and TinyMCE 6.x-1.x-dev. When I create the first profile, the following error occurs:

warning: Invalid argument supplied for foreach() in C:\Program Files\drupal\includes\form.inc on line 1181.

The code is the following in

 /*...*/
    $form += array('#default_value' => array());
    foreach ($form['#default_value'] as $key) {
      $value[$key] = 1;
    }
/*...*/ 

and var_dump shows that #default_value is NULL. All starts from tinymce_profile_form() so it's about TinyMCE. I guess the problem is using PostgreSQL 8.3 but I need directions how to continue in reporting or fixing this.