Identical printers, sub backend

[Fernando]

> We *may* be able to improve the standard USB backend with support
> for libusb in CUPS 1.4; until then there is nothing we can do since
> we can't map the information in /proc to the corresponding device
> filename... :(
Ok.

What about deviceURIs in the form usb:/dev/usb/lp0?
IIRC in the docs there is a reference to this form of device specification, but I can't get this to work in any of my (Debian) boxes. It's not supported anymore?
Thanks,
Fernando