disable SACK tcp option

[Paul]

        Hi;

        Ive just gotten the hurd installed, and networking up.
I want to flesh out the skeleton with apt, but the tcp SACK
option is enabled.
        Now, just believe me, that from where I am, that is
bad. It causes connections to randomly stall forever. I have
to turn it off on all my boxes, and have had to ever since they
started turning it on by default under linux.
Its beyond my control.
        So, how can I turn this option off? Google is giving
me _nothing_ ...

Thanks;
Paul
set@pobox.com
(please CC me if I am lucky enough to get a reply)