[link|http://z.iwethey.org/forums/render/content/show?contentid=209765|#209765].
Hmmm. But you seem to be using it already.
I dunno. I haven't seen a popunder since I installed Flashblock (using Firefox 1.0.4 with Adblock v0.5d2 Nightly * build 39). I hope it's nothing new. :-(
Luck!
Cheers,
Scott.