bug#2344: 23.0.90; disappearing cursor on Mac OS X

I've run into a disappearing cursor problem with latest gnu emacs
from cvs on Mac OS X.

emacs/nextstep/Emacs.app/Contents/MacOS/Emacs -Q

find-file ~/
move cursor with arrow keys to some file name
move mouse around so that the file name is highlighted in green
move mouse away
the cursor is gone.

sometimes it reappears after a couple of seconds, sometimes it takes
moving the mouse around a different part of the buffer to get the
cursor to reappear, but repeating the above steps would make the
cursor disappear again, and often it does not reappear unless the
cursor is moved, say, with the arrow keys.



In GNU Emacs 23.0.90.1 (i386-apple-darwin9.6.0, NS apple-appkit-949.43)
 of 2009-02-13 on dhcp-0012515396-a9-da.client.fas.harvard.edu
Windowing system distributor `Apple', version 10.3.949
configured using `configure  '--with-ns' '--without-x''