/**
  * Modify the address book of this address.
  *
  * This can only be done if the address book already accepted
  * the address as one of it's addresses.
  *
  * @param UcAddressesAddressBook $addressBook
  *   The address book to move this address to.
  *
  * @access public
  * @return boolean
  *   TRUE on success.
  *   FALSE otherwise.
  */
 public function privChangeAddressBook(UcAddressesAddressBook $addressBook)
 {
     foreach ($addressBook->getAddresses() as $address) {
         if ($address === $this) {
             // Address appears in address book, changing address book approved.
             $this->addressBook = $addressBook;
             return TRUE;
         }
     }
     return FALSE;
 }