On Mika's, it looks like a total of 1411 blocks have been submitted under this incorrect ID, and started showing up on January 8, 2001. If you added any new machines on that day, please check and make sure that they have the correct ID, as your work is not being properly credited to the Cavalry!
Edit: Just looked up this ID on Dnet and it looks like this account has actually been active there since December 18th, with a total of 4,250 blocks submitted...