I have this card installed and it is probed as follows.

wm0 at pci2 dev 10 function 0: Intel i82544EI 1000BASE-T Ethernet, rev. 2
wm0: interrupting at irq 11
wm0: Ethernet address 00:02:b3:c8:1d:42
ukphy0 at wm0 phy 1: Generic IEEE 802.3u media interface

If I configure it with media auto it works at 100Mb even though it is plugged 
into a Gb switch port.  If I set media to 1000baseT then it doesn't work at 
all.  I get no carrier and no light.  Oddly enough, at 100Mb it seems to be 
set for 1000Mb, at least according to the lights.  The ifconfig shows:

wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        capabilities=7<IP4CSUM,TCP4CSUM,UDP4CSUM>
        enabled=0<>
        address: 00:02:b3:c8:1d:42
        media: Ethernet 1000baseT
        status: no carrier
        inet 192.168.11.205 netmask 0xffffff00 broadcast 192.168.11.255

I don't recognize that "enabled=0<>" line.  Is there something else I need to 
do for this that I don't have to do for 100Mb?  The man page doesn't mention 
anything other than the media types.

My ifconfig.wmo has this:

up
192.168.11.205 netmask 0xffffff00 media 1000baseT

-- 
D'Arcy J.M. Cain <darcy@netbsd.org>
http://www.NetBSD.org/