Today Nintendo officially announced that there are bugs in the Japanese versions of Diamond and Pearl. Version 1.0 of Diamond and Pearl has a bug that allows you to catch Sheimi, Darkrai or Aruseus. The exploit: By surfing through the very first door of the 1st elite four, you literally surf through the door. Walk around Shinou in the dark until you reach the islands where these legendary Pokemon are hiding.

Quote from Bulbanews:
Glitch A
After entering the Union Room on the second floor of the Pok