Fool-proof way of ID'ing a 1080 progressive signal on a HD set?

This is a issue with the current crop of HD TV's that can accept a computer signal thru HDMI.
There doesn't seem to be a positive way to confirm if the set is displaying an interlaced or progressive signal.
I know that isn't a issue with dediciated computer monitors (LCD displays in particular), but with Microdisplays (DLP, LCD & LCoS RPTVs') it is. There is one set that has been confirmed, but there are others that no one can say one way or the other.

Resolution isn't a problem, it's just the 'i' vs 'p' issue.

Is there some s/w program that is a 3rd party to ATI and nVidea that will positively tell if the display is interlaced or progressive?

Well in standard def, when you play video back, you can tell just by watching full motion video. I'd imagine you could tell in HD, too.

I will make motion look buttery smooth
P will make it appear choppy, like movies in the theater.

You can usually get an idea of I vs. P when you pause video, also. If you get flicker on pause, it's probably I.

That's ok if you are watching something you recorded, but 'live TV' it won't help.
Anyways, I'm referring to a computer output.