HEADS UP: ULE off in 5.3

All,

A lot of poeple have noted recently that a lot of bug reports are
coming in with strange symptoms, and only after a lot of detective
work does it turn out that the submitter is using the ULE scheduler.
We turned off the ULE scheduler months ago and tried to make it
clear that it has problems and is not considered stable.  Since
there are likely many people out there that might not be aware of
what scheduler they are using, I've set the ULE source code to error
out and not compile at all for RELENG_5 and RELENG_5_3.  The time
spent debugging ULE-induced problems is causing way too much lost
time, and we need to focus on debugging the supported configurations,
not the unsupported ones.

Scott