Problem during install 3.4 (ethernet)

[James Stocks <stocksy@stocksy.co.uk>]

I hope this is an appropriate question for the list.  I'm completely 
new to *BSD and I'm trying to install OpenBSD 3.4, following the 
directions here http://www.uk.openbsd.org/faq/faq4.html

I'm fine until it comes to network configuration, it just doesn't want 
to talk to my ethernet card.  It's a Netgear FA312 using the National 
Semiconductor DP83815 chip, which I understand should work OK with 
OpenBSD.

This is what I get:

IP address for sis0? (or 'dhcp') dhcp
Issuing hostname-associated DHCP request for sis0.
Internet Software Consortium DHCP Client 2.0p15-OpenBSD
Listening on BPF/sis0/00:a0:cc:a2:d1:d5
Sending on   BPF/sis0/00:a0:cc:a2:d1:d5
Sending on   Socket/fallback/fallback-net
DHCPDISCOVER on sis0 to 255.255.255.255 port 67 interval 1
DHCPDISCOVER on sis0 to 255.255.255.255 port 67 interval 2
DHCPDISCOVER on sis0 to 255.255.255.255 port 67 interval 4
DHCPDISCOVER on sis0 to 255.255.255.255 port 67 interval 10
sis0: watchdog timeout
DHCPDISCOVER on sis0 to 255.255.255.255 port 67 interval 13
sis0: watchdog timeout

...and so on until it gives up.  I can't get a connection if I 
configure the card manually either.  This is a problem because I wanted 
to do an FTP install.  The card seems to be good, it works under Debian 
and XP - I can obtain a DHCP lease no problem.  Any help or suggestions 
offered gratefully received.