Yes, I’ve seen the same problem.
At first I thought it might be related to the ProRes/Kona LHe issue but I’ve also seen it on another machine with CS5 and no Kona card.
I also thought it might be because I have CS4 and CS5 on the same machine but again, the other machine with a clean install and only CS5 still exhibited the problem.
I have found a workaround…
When you’ve Added to Render Queue and chosen ProRes422, go into [Codec Settings] and check then uncheck the Interlaced boxed then click OK.
I have found this ensures the output is progressive.
This works on both machines I have tried it on. Please let me know if this works for you.