Original: In 1.2.1 (Can confirm this does happen in 1.2), while moving and attempting to open a door, it will open multiple times extremely fast. Standing still and opening works as intended
I was using an Oak Door in Survival if that helps, haven't tested with others

Edit: Can confirm this also applies to placing blocks and torches. Interacting with Doors, trapdoors, fence gates, rotating items in item frames, bed messages (too far away, can only sleep at night), Redstone comparators, Redstone repeaters, levers, spawn eggs, fireworks, daylight sensors. Sound doubles up when placing lava and water while moving