I am using redhat 9 for the desktop machine and zynergy 1.1 for the zaurus. It turns out that /etc/hotplug/usbdnet is not needed on redhat 9. It automatically starts the usb0 interface as long as you have the correct settings in ifcfg-usb0. My problem is with the zaurus. /etc/hotplug/net.agent gets called when the zaurus is inserted in the usb cradle, but for some reason, unregister gets called first before register. I found this out by inserting a flite command in both the register and unregister parts of usbdnet. The zaurus cannot anticipate when I will remove it from the cradle, so I need something that is triggered by removal of the zaurus from the cradle. Basically, when I put the zaurus on the cradle, I want ntpdate to run, take down shorewall and shut down ipsec, tell wwwoffle that it is online. When I remove the cradle, I want the zaurus to remove the usbd0 interface, tell wwwoffle that it is offline.