That was what a K-7 user originally reported:-
http://forums.dpreview.com/forums/read.asp?forum=1036&message=32532703
He encountered problems under specific conditions in dialling the Tv (Time Value) into his K-7. When turning the e-Dial, the Tv is not descending nor ascending in the normal stepping as it should be. And he also said that in one of his follow-up responses, "Hmm, its seems to work OK after switching between modes. But my main trouble was on M mode, low light situations. While scrolling it was just skipping around. "
But it seems that this problem is not isolated, as another K-7 user who has replied in the thread also said the same, "Hmmm... I ran into this a week ago when I used a 2 stop neutral density filter to try to get a longer exposure in M mode. The shutter speed wheel bounced around erratically between 320 and 8000 when I wanted 1/10 sec or slower. Very perplexing and frustrating. "
So, would this be a firmware bug or it is just that individual K-7 units that are defective? The former case is just a software issue that should be fixed whilst the later case would be caused by any quality issues at the Pentax factory. But I guess it is more likely to be the former case as those K-7 users reported that the e-Dial for entering Tv was working for some other operation modes.
Indeed, it would not be surprised to see the firmware of those newer Pentax DSLRs are having (firmware) bugs that shouldn't exist as those are related to the very basic operations of a camera. But then it does happen more frequently with recent bodies, just see the latest silly K-m bug that another Pentax user and I have discovered last time.