how does over the air epg work?

[1234567]

Forgive my ignorance, but I've only had a hdtv for about a month or so, so I am rather new to all these features. I noticed that somehow the epg can gleem information from the air waves about the programming. Sage fills in empty spots that the internet zap2it left blank by appearantly using this. My tv itself displays information about the show when I press a button on my remote. Why it's kind of neat. Anyway, the online epg information has some kind of issues about getting information for public television so if I visit that channel, sage some how gets info for that day. Sounds good so far, right? Well, the problem is that the info it gets is often wrong, and has these blank spots with nothing, not even DTV program or NO DATA, so you can't get sage to play that channel. And, if by chance you read my earlier post about my PC not being able to sleep because the wiz.bin file gets screwed up, you might realize that I suspect the weirdness has something to do with this.

So, my question is this, does this info broadcast with the digital shows? Or, is it broadcast from some other repository of information? I guess where I'm going with this is would my local station be the place to register a complaint? I know in the FAQ it mentions letting sage know about it, and I probably will, but if it irritates me too much, at least I can pick up the phone and call my local station.

Thanks