[Soekris] console hang/pxebooting OpenBSD 4.4

[jmc]

i have a couple of 5501s i'm attempting to upgrade. `upgrade' is
probably not the correct term in the OpenBSD world. i'm installing 4.4
over 4.3.

at any rate, i copied the pxeboot and bsd.rd images into my tftp root.
in the Soekris boot monitor, i type `boot f0' and since i don't have a
boot.conf in place in my tftp root, i set up the console tty by hand.
namely:

set tty com0
stty com0 19200

and then just a `boot bsd.rd'

my console (using cu(1) on a newly upgraded 4.4 box) just hangs thusly:

http://www.cosimano.us/~jmc/hang.png

if i drop the pxeboot image that was supplied with 4.3 back in my tfp
root, the normal expected behavior returns.

you'll note on the png above that the pxeboot version is 2.03, while the
version of pxeboot included with 4.3 is 2.02.

so is it correct to assume that something changed in pxeboot that i need
to adjust for?

anyone else stumbled upon this? if there's anything i should be doing to
troubleshoot this further, i'd appreciate hearing about it.

--john