/**
* Return the new internal state for this attribute.
*
* @param array $changes The object data that should be updated.
*
* @return array The resulting internal state.
*
* @throws Horde_Kolab_Server_Exception If storing the value failed.
*/
public function update(array $changes)
{
$changes = parent::update($changes);
if (!empty($changes)) {
throw new Horde_Kolab_Server_Exception(sprintf("The value for \"%s\" may not be modified!", $this->_name));
}
return $changes;
}