3C905B-TX problems on fresh install

[Dana Baguley]

Hi, I'm a FreeBSD Newbie. I've had some experience with Linux,
particularly Gentoo. I'm running a computer that I've installed
FreeBSD on behind a router that's connected to my DSL modem. The
router provides DHCP for all the 3 computers on my home network.
Everything works fine with the other computers and everything worked
fine on this computer when I was running Gentoo on it. My NIC is a
3Com 3C905B-TX. My motherboard is a EPOX EP-3VBA. When I installed
FreeBSD I wanted to use FTP, but the DHCP step didn't work so I
installed from CD. Now whenever I boot up I get the error message
"xl0: watchdog timeout" repeatedly when dhclient starts up, when sshd
comes up, and occasionally after boot at seemingly random times. I've
noticed when I get this error that my link light goes off for a little
over a second. I can only ping the localhost. Also I get an error with
the date, time, name of my computer, and "inetd[435]: ssh/tcp: bind:
Address already in use" every ten minutes. netstat -rn shows 10.0.0.1
(the router) as the default gateway and 127.0.0.1 as the gateway for
10.0.0.100, the address assigned by the router. The correct MAC
address for the router shows up as the gateway for 10.0.0.1.  The
computer shows up on the router's DHCP clients table. ifconfig -a
gives me

xl0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=9<RXCUM,VLAN_MTU>
        inet6 fe80::210:5aff:fe09:f53e%xl0 prefixlen 64 scopeid 0x1
        inet 10.0.0.100 netmask 0xffffff00 broadcast 10.0.0.255
        ether 00:10:5a:09:f5:3e
        media: Ethernet autoselect (100baseTX <full-duplex>) 
        status: no active
plip0: flags=108810<POINTTOPOINT,SIMPLEX,MULTICAST> mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
        inet 127.0.0.1 netmask 0xff000000
        inet6 ::1 prefixlen 128
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3

I don't know what to do to get networking working on this computer.
Any ideas? Thanks in advance for your help!

Dana Baguley