zfs problems after rebuilding system [SOLVED]

[Pete French]

> I based my fix heavily on that patch from the PR, but I rewrote it
> enough that I might've made any number of mistakes, so it needs fresh
> testing. 

Ok, have been rebooting with the patch eery ten minutes for 24 hours 
now, and it comes back up perfectly every time, so as far as I am 
concerned thats sufficient testing for me to say its fixed and I would 
be very happy to have it merged into STABLE (and I;ll then roll it out 
everywhere). Thanks!

-pete.