Вот оно для Drupal 7 и Drupal 6 .
Для D7:
<?php
// Retrieve the default values for 'value' and 'format', if not readily
// available through other means:
$defaults = array(
'value' => '',
'format' => filter_default_format(),
);
$my_richtext_field = variable_get('my_richtext_field', $defaults);
// Just construct a regular #type 'text_format' form element:
$form['my_richtext_field'] = array(
'#type' => 'text_format',
'#title' => t('My richtext field'),
'#default_value' => $my_richtext_field['value'],
'#format' => $my_richtext_field['format'],
);
?>
Для D6:
<?php
// Your saved or new data is supposed to have a value and a format. Just like
// $node has a $node->body and $node->format. May also come from a
// variable_get('mymodule_admin_setting', array('value' => '', 'format' => NULL));
$mydata = mymodule_data_load();
$form['myfield']['mytextarea'] = array(
'#type' => 'textarea',
'#title' => t('My textarea'),
'#default_value' => $mydata->value,
);
$form['myfield']['format'] = filter_form($mydata->format);
?>