Interesting high dan tsumego

[Josh Hatch]

Here's an interesting tsumego which has recently stumped a good friend on KGS recently. From a somewhat recent Japanese problem book for dans. Enjoy
Black to move

$$Bc
$$ | . . . . . . . . . . .
$$ | . . . . . . . . . . .
$$ | . X X X X X X X . . .
$$ | . X O O . O O X . , .
$$ | . X O . O . O X . . .
$$ | . X O . . . O X X . .
$$ | . X . . O . X . . . .
$$ +-----------------------

Click Here To Show Diagram Code

[go]$$Bc
$$ | . . . . . . . . . . .
$$ | . . . . . . . . . . .
$$ | . X X X X X X X . . .
$$ | . X O O . O O X . , .
$$ | . X O . O . O X . . .
$$ | . X O . . . O X X . .
$$ | . X . . O . X . . . .
$$ +-----------------------[/go]

I thought I recognized this problem. Tien had this problem when he was an insei in Japan and posted about it on his blog. http://gooften.net/2011/12/06/sample-insei-tsumego/
There's some discussion of the problem in the comments on his post.