OK. As I wrote earlier I've been experimenting with OF scripting to make it recognize disks with long spin-up time. After some problems (screwed up nvramrc) I have found the solution that works for me. What I did is a small script added to nvramrc that adds the slight delay (3-4 seconds) to the boot-up process. The delay is enough for my disks to spin up so I can use auto-boot without reseting Pegasos on cold boot up.

First of all I want to warn enyone trying to use it - it can make your Pegasos unbootable and you'll need to reset nvram settings using emergency procedure described here (in case of screwed up nvramrc you need to press ESC on serial console to get to the IKARUS low level console). I won't take any responsibilty for any damage you could do to your Pegasos or yourself.

After that warning here is what I did.

0. My setup is Pegasos II G4 1GHz with the newest OF (2004-05-04), two disks (Maxtor 200GB and WD 80GB) on primary IDE channel.
1. Boot up to OF prompt
2. Open nvramrc using nvedit command
3. You'll see the simple text editor. At the beginning enter the following:

: wait 500000 0 do i drop loop ;
wait

Mind tha spaces - it must be exactly as above.
Press CTRL+C to exit the editor
4. Save nvramrc to nvram using nvstore command
5. Power down, wait for the disks to spin down completely and then power it up again. It should boot up normaly with a slightly longer delay before prompt. After that you can try ls /ide - it should show your IDE disks - hopefully detetectd correctly.

Above procedure worked for me - I hope someone brave enough to try will find it usefull to.