Supplemental Result Ban?

Cloaked pages are listed as supplemental result.

[rankboy]

Hi guys,
I have been cloaking for quite some time now and have been seeing decreasing results for the past few years. My main question is in Google. Almost all of our cloaked pages are listed in the engine as Supplemental Result. This of course drops them down in the rankings to the point you can only rank for the ultra obscure terms. I'm mainly wondering if anyone else sees the same things with their cloaked pages.
In addition, all our pages use IP based cloaking that is kept up to date by a few reliable services. Do you think you get tagged as supplemental for on page factors, or if they detect some kind of cloaking activity, i.e. mismatch eTags, missed spider, etc.

[LeoXIV]

yes i am seeing that, i am suspecting that Google is using its proxy caches to compare with gbot results, hence the detection.

[rankboy]

I'm wondering if data from the toolbar helps detection. It seems like the best way for them to tell if a user was given a different page than was cached.

[volatilegx]

I too believe they may be testing using Google toolbar/accelerator data to help find cloaked pages. It's what I would do if I was them.

However, I believe that if they find cloaked pages, they simply drop them completely from the index rather than sending them to the supplemental index. It's more likely you have linking problems, meaning not enough links from trusted, on-topic sites.