Actually, I didn't mean to make such a terse post. I was called away before I could edit it.
That excerpt is from my notes on setting up a few 5120's which I assume are very close to the 5140's. The "secret" is probably the line:
set /HOST/bootmode script="setenv auto-boot? false"
The line "set /HOST/diag trigger=none" disables some lengthy diagnostics. This is not required to get to the OK prompt, but it will get you there faster. It might be wiser to run the diagnostics at least once, but, for better or worse, I don't.