HW vs SW cursor confusion

[McDonald, Michael-p7438c]

  We have our own driver based upon the fb/dummy drivers. Everything
works as expected as long as we use the SW cursor. If we choose the HW
cursor, it works fine (it's invisible because none of our HW cursor
routines actually do anything! (except UseHWCursor which returns True))
until the first time any app sets it's own cursor, xterm for example.
Once that app runs, the cursor reverts to using the SW cursor routines
and the cursor becomes visible. We've also compared our driver to the
intel/i810_[cursor|driver].c code and we can't find anything obvious.

  Why is the server reverting to using the SW cursor? ie what did we
screw up?

Mike McDonald