public function testManualIterator()
{
$message = new Zend_Mail_Message(array('file' => $this->_file));
$this->assertTrue($message->valid());
$this->assertEquals($message->getChildren(), $message->current());
$this->assertEquals($message->key(), 1);
$message->next();
$this->assertTrue($message->valid());
$this->assertEquals($message->getChildren(), $message->current());
$this->assertEquals($message->key(), 2);
$message->next();
$this->assertFalse($message->valid());
$message->rewind();
$this->assertTrue($message->valid());
$this->assertEquals($message->getChildren(), $message->current());
$this->assertEquals($message->key(), 1);
}