OF boot delay to allow disk to come alive?

[Georg Schwarz <georg.schwarz%freenet.de@localhost>]

I'm running NetBSD on a PowerMac 7300 (Open Firmware 1.0.5) with a  
Seagate ST39173N SCSI disk at SCSI ID #0 to boot from.
I've set boot-device to scsi-int/sd@0:0
When I power up the PC OF immediately complains : can't OPEN scsi-int/ 
sd@0:0
However, upon a further soft reset via the keyboard it boots  
flawlessly. I suspect that the disk needs a few moments to come alive  
upon being powered on.
Is there a way to introduce a startup delay for OF to make it wait,  
say, 5 seconds before trying to access the boot disk?
The way it is right now I think the machine would not be able to boot  
up unattendedly.

--
Georg Schwarz    http://home.pages.de/~schwarz/
georg.schwarz%freenet.de@localhost  +49 151 11559652