According to Pokemon.com there's been a Manaphy Event all October long. So if you don't have Pokemon Ranger now's your chance to get Manaphy!!

Also, if anyone does successfully get Manaphy through this event, tell me. My cousin tried to get it but that Mystery Gift signal didn't appear when he tried it. After he tried to get his Mystery Gift via Wireless it just kept searching for a gift without one ever being found. It didn't quit searching though.