O2 post-install boot: Requires serial console, is already on one

["Jos Purvis" <jos%melete.org@localhost>]

[Resending due to accidental HTML formatting]

Hi, gang,

Dusting off an O2/5000 here, and having some trouble trying to get
NetBSD running on it. The installation process goes like clockwork:
perfect CDROM boot, disk partitioned, packages installed happily. When
the system boots, though, I get this:
++++++++
NetBSD/sgimips 4.0.0_PATCH Bootstrap, Revision 1.2
(builds@wb24, Tue May  6 03:51:34 PDT 2008)

devopen: pci(0)scsi(0)disk(1)rdisk(0)partition(0) type scsi file netbsd
3314352+192508 [187408+179270]=0x3b1ed0
[ Kernel symbol table missing! ]
panic: ip32 supports serial console only.  sorry.
nullvoid
Stopped in pid 0.1 () at        0x882c0774:     jr      ra
                bdslot: nop
db>
++++++++

The problem is that the system IS on a serial console: I've done the
entire installation and reboot process over Serial1, and everything
goes swimmingly up to that point. I've tried this with 4.0-RELEASE and
4.0-CURRENT (the snapshot posted above), and get exactly the same
results both times. Anyone seen this?

Happy to post hinv/printenv if it'll help!

Cheers,

Jos