MultitechMT5634ZPX-PCI-NV-V92

Does the Multutech MT5634ZPX-PCI-NV-V92 work in FreeBSD? Early days yet, but no problems so far. It's recognized as a =sio= device. Here's what I see from dmesg:

sio0:  port 0x9000-0x9007,0x9400-0x94ff,0x9800-0x98ff mem 0xe5800000-0xe58000ff irq 10 at device 15.0 on pci0
sio0: moving to sio4
sio4: type 16550A

I have two serial ports on this particular machine, so I presume that's why it's moving it to sio4. After that, I can run:

cd /dev
sh MAKEDEV cuaa4

and then:

$ cu -l /dev/cuaa4
Connected.
ATI0
LT V.92 1.0 MT5634ZPX-PCI-V92 Internal Data/Fax/Voice Modem Version 1.25p
OK

Sweet! But wait, what's this in =/var/log/messages=?

sio4: 148 more interrupt-level buffer overflows (total 148)
sio4: 200 more interrupt-level buffer overflows (total 348)

Ack! Is my 3133+ modem trying to R00+ m3? Quick Google turns up PR 51982, which suggests editing =sio.c= judiciously. After doing that, I can run the same command (=ATI11= while connected via =cu=) and no nasty output. Sweet!