I don't know for sure, but maybe it's my shiny Crobat that I caught as a Zubat in my Diamond version on April 23, 2007 (FYI, the day after Diamond and Pearl's release date). There might have been some imports of older Pokémon, but most of them got deleted when my Wii got bricked (they were in My Pokémon Ranch), and yes, I have hacked my Wii (that's why it got bricked). Still, there were some things I left in my Diamond version, but I'm too lazy to go check right now.