Sun Enterprise 4500 SCSI boot freeze

Hello!

	I'm having problems with my Sun Ultra Enterprise 4500 connected to a
StorEdge S1 disk array. After a successful installation of OpenBSD the
machine seems to boot correctly around 1/4 the time - when it doesn't,
it freezes and is completely unresponsive, even to sending break signals
(I am connected to it via ttya). The boot message log can be found here:
http://hpaste.org/51037
	When it does boot correctly (I don't have a dmesg available now, since
it's in a remote location and can't try to boot it again without going
there...) all seems to work well, except for the disk performance - I
can write with max. 2MB/s, which seems very bad.
  The box was running Solaris 11 express before, which booted without
problems and had a (not astonishing, but given the 20MB/s ultra-scsi cap
also not bad) ~12MB/s write performance.
	Is there any way to resolve this issue? What could be causing it?

-- 
regards,
WiesEaw 'herself' Kielas