usb to ps/2 adapter works in one machine, but not another?

[Torfinn Ingolfsen]

Hi,

Many new machines / motherboards  today comes with only one ps/2 port.
Well, the kvm switches I use still has ps/2 ports. Therefore I use
adapters that plug into a usb port and gives me two ps/2 ports.
Like the Slim USB 2.0 to PS/2 Adapter Dongle (sku 1440)[1] from DX.
I generally only use one port on these - for a mouse.

On a Asus V7-P7H55E[2] it works nicely. Detection in dmesg looks like
this:
Mar 13 17:13:08 kg-v7 kernel: ugen1.4: <GASIA> at usbus1
Mar 13 17:13:08 kg-v7 kernel: ukbd1: <GASIA PS2toUSB Adapter, class 0/0, rev 1.10/2.80, addr 4> on usbus1
Mar 13 17:13:08 kg-v7 kernel: kbd3 at ukbd1
Mar 13 17:13:08 kg-v7 kernel: ums1: <GASIA PS2toUSB Adapter, class 0/0, rev 1.10/2.80, addr 4> on usbus1
Mar 13 17:13:08 kg-v7 kernel: ums1: 5 buttons and [XYZ] coordinates ID=1

The machine runs FreeBSD 8.0-stable / amd64:
root at kg-v7# uname -a
FreeBSD kg-v7.kg4.no 8.0-STABLE FreeBSD 8.0-STABLE #1: Fri Mar 12 19:56:45 CET 2010     root at kg-v7.kg4.no:/usr/obj/usr/src/sys/GENERIC  amd64

But on a Gigabyte GA-MA74GM-S2H[3] it doesn't work, even if detection looks similar:
Mar 13 17:43:06 kg-f2 kernel: ugen0.2: <GASIA> at usbus0
Mar 13 17:43:06 kg-f2 kernel: ukbd0: <GASIA PS2toUSB Adapter, class 0/0, rev 1.10/2.80, addr 2> on usbus0
Mar 13 17:43:06 kg-f2 kernel: kbd2 at ukbd0
Mar 13 17:43:06 kg-f2 kernel: ums0: <GASIA PS2toUSB Adapter, class 0/0, rev 1.10/2.80, addr 2> on usbus0
Mar 13 17:43:06 kg-f2 kernel: ums0: 5 buttons and [XYZ] coordinates ID=1

This machine also runs FreeBSD 8.0-stable  / amd64:
root at kg-f2# uname -a
FreeBSD kg-f2.kg4.no 8.0-STABLE FreeBSD 8.0-STABLE #3: Fri Mar  5 18:16:51 CET 2010     root at kg-f2.kg4.no:/usr/obj/usr/src/sys/GENERIC  amd64

One machine has an Intel usb chipset, and the other an ATI usb chipset, but shouldn't it work anyway?

References:
1) http://www.dealextreme.com/details.dx/sku.1440
2) http://sites.google.com/site/tingox/asus_v7-p7h55e
3) http://sites.google.com/site/tingox/ga-ma74gm-s2h
-- 
Regards,
Torfinn Ingolfsen