ZyXEL Omni 56K Plus USB/serial modem

[perryh at pluto.rain.com]

Has anyone tried, either successfully or not, to
use a ZyXEL Omni 56K Plus modem with recent FreeBSD?
It's listed in /usr/src/sys/dev/usb/usbdevs, and
thus in usbdevs.h and usbdevs_data.h, but I found
no other mentions of ZyXEL in the kernel source
and none at all in the handbook.  (The comments in
/usr/src/sys/dev/usb/usbdevs point out that simply
having an entry there does not mean that any driver
will necessarily recognize the device.)

I'd prefer to connect it via USB if that will work,
but the modem also supports serial connection.