Okay, I have a problem which sounds complex, but I'm hoping it's not.

My e-smith gateway has a Kingston KNE110TX network card for the local LAN.
It is connected to a Kingston 8 port 10/100 switch (KNS800/WG) using the tulip driver. (yes it always negotiates it's 100BaseT speed properly, though doesn't often negoiate Full Duplex, only half.)
However, if it gets unplugged from the switch, plugging it back in does not put it back on the network!
It cannot ping other machines, and other machines cannot ping it.
The fix is:
ifdown eth1
ifup eth1
ping 192.168.1.xx -- where xx is another ip on the network.
Only then does it seem to be visible again to everyone.
This is not a good solution because I don't have a keyboard or monitor for that machine, and would like to just keep it in a closet with the cable modem. Other machines seem to have no problems when I unplug them from the switch, that is why I'm writing to the e-smith forums.
Does anyone have any ideas? I would have assumed that Kingston would be about as good as it gets and that I couldn't go wrong with them.
Is this an e-smith thing or a hardware thing?
Thank you very much!
Matt