Lock-free Hashtable anyone?

Hi,

Anyone know of an available lock-free hashtable implementation? I've found
the following:

http://code.google.com/p/nbds/ (Alpha version last updated 2009)
http://www.sunrisetel.net/software/devtools/sunrise-data-dictionary.shtml
(Claims
lock-free but looking at source it seems not so.)

Currently I'm using Click's Hasktable with my own locks to sync between
multiple threads. This scales alright with lookups, inserts and deletes,
but iterating over large tables does not scale at all.

So what are you guys using? Do you know of any alternative lock-free
hashtable implementations out there?

Cheers

Beyers Cronje