I found this interesting. It was in David Pogue’s column last week. He’s the New York Times Technology writer:
Q: David: I’ve noticed this for a year, and have not been able to get Microsoft to change it: Type "Obama" or "obama" in Microsoft Word or Outlook, and the spelling checker recommends "Osama" as the corrected spelling. How could this continue month after month, especially now that Mr. Obama is likely to be the Democratic candidate for president? Hope you can connect with appropriate folks at Microsoft and get this changed.
A: Well, it does seem like a silly glitch. But I’m not sure even I could convince Microsoft to release a new version of Microsoft Office software just to correct a single entry in the spelling dictionary. But if it helps, here you go: How about it, Microsoft?