AT&T blocking Dell Streak beta units? (update: SIMs were deactivated, phones weren't supposed to be sold)

There's a fascinating discussion going on over in MoDaCo's forums today suggesting that Dell Streak units that were given out recently as part of the company's US beta test in and around Austin, Texas are no longer functioning on AT&T, the result of an apparent IMEI block; voice calls placed from the devices all get re-routed to AT&T customer service, and 2G / 3G data doesn't work at all. Our understanding is that beta testers were allowed to keep their units after the conclusion of the test period -- some of those ended up on eBay, naturally, so you can imagine that buyers are probably feeling a little steamed by this. One user has had luck with data by using the iPad's APN and plan settings, but otherwise, there seems to be a bit of frustration going around. We've reached out to AT&T to figure out what's going on; we'll let you know when we have more.

[Thanks, Reece M.]

Update: We've had at least one buyer of a beta unit write in to tell us that his Streak is still functional, so it seems that the IMEIs haven't been blocked across the board -- so far, anyhow. Leave us your experiences in comments, won't you? Thanks, Josh G.!

Update 2: Dell just wrote in to give us some more background on the situation, and it looks like at least part of the confusion is stemming from the fact that the Streaks were provided with 30-day SIMs from AT&T; testers were provided with the following tidbit on the fate of their phones after the SIMs expired:

"You can still use your Streak. Your beta phone number will be disconnected tomorrow, but you'll continue to have access to all the cool Streak features including the Android marketplace, games, email, Facebook, etc., you'll just need to connect via WIFI. Your Streak, while it may function on some carrier networks, is a beta phone and is therefore not certified on any carrier network, so it may not function normally. Any such use will be subject to and your carrier's data and voice plan."

More importantly, it turns out that the agreement testers signed specifically forbade them from selling their Streaks, so it seems like it'd be entirely within Dell's right to report the IMEIs missing or stolen to AT&T -- not to say that ever occurred, but in light of the agreement, it wouldn't be out of the question.