pdaXrom already has driver support for pegasus and rtl8150 based usb ethernet adatptors. Others may or may not be supported, but as those 2 were the only ones I had at my disposal they were the only 2 tested.
To get this working you need 2 new files:
these are based on:
respectively. However eth.func fixes several typos in the original usbd.func which prevents it from working properly (the process for shutting down an interface hangs).
And 1 modified file:
Basically the original net.agent didn't look for ethX devices, and as both my adaptors appear as eth0 net.agent just ignored them. I essentially duplicated the code which handled the usbdX devices and modified it slightly to work with ethX devices.
The 3 files are in the attachment (remove the .txt extension). Make a backup of the original /etc/hotplug/net.agent (just in case!), then extract the 3 files and copy them into /etc/hotplug/. Modify /etc/hotplug/eth.conf to your liking then plugin your adaptor and enjoy
PS If there are easier/better ways to achieve this please let me know!