Since nobody seems to have an idea of what has gone wrong, I'm going to download and install the "official" 4.6.1.114 from tmobile.com, and then try to upgrade to 4.6.1.239 (since I can't find .250). This 8900 that I have was bought on ebay, unlocked, and although it came in a T-Mobile box, maybe there's some quirk in the OS from the unlocking that's causing it to refuse the upgrades. Does this sound like a reasonable approach?

Ubizmo