Guillaume - awesome!
Totally in the right direction!
Do you want to apply on codehaus xircles for contributor status and then you can have direct access to the
jetty-contrib svn. You would still need to run patches to jetty-core through me!
I have not gone totally over your code yet, but have seen a few little items of concern... but I will
double check before I expand on them. I have not used the concurrent mechanism much before and
am cautious about things done outside of big safe synchronize blocks 
I will also start work on a proxy handler that uses this, which will be a good test of it.
Anyway, patches have been committed. THANKS A MILLION!
Patch to the NIO layer to support client connections