Knapsack-based cryptosystems

[Eamon Daly <eamon@cosc.canterbury.ac.nz>]

Some convoluted questions for knowledgeable c'punks:

What's the state-of-the-art in cryptanalysis of knapsack-based
cryptosystems? I know the fate of Merkle-Hellman, Graham- Shamir
etc. as written by Brickell and Odlyzko in _Contemporary Cryptology_
(edited by Simmons). What of the Chor-Rivest cryptosystem (I'm aware
of the attack in Eurocrypt 95)? Finally, has any work been done on
cryptanalysis of the dense compact knapsack-based cryptosystem of
Glenn Orton? ("A Multiple-Iterated Trapdoor for Dense Compact Knapsacks"
in _Eurocrypt 94_)

Thanks for any information.

Eamon Daly