A couple of days ago I had the wierdest error. We have added some fields on Acccount and a new entity called Billing Account so that there is Contry and Country Code in both. The wierd thing was that when I opened the tab with the field, after about 1 second, the country changed to "United States" and the country code to "1". This even happened to the custom entity.
Well, that just teaches you, don't install a lot of crap into IE. :)
Microsoft Dynamics CRM Chief Architect