At the last ISP I worked at, the C programmers spent a few days trying to figure out how to kill off open conections, and couldn't find a way. This doesn't mean it ain't there, but it's well hidden.

As for lowering the close timeout, you can recompile your kernel (assuming you have the source :) and change the socket timeout to anything you want. I don't know the effects of changing the timeout, but I feel a great inertiea when it comes to monkeying with TCP.

It is actually fairly easy to fake the responses by monitoring the connections, and then 'injecting' a fake close response at the right time. However this is an unappealing practise.

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Jeremy
I didn't believe in evil until I dated it.