Slow reverse incremental search on mac os x

[Torbjørn Hergum]

Hi

When I do a reverse incremental search on my mac with os x, it seems to 
hang for several seconds before starting the search. Forward search is 
snappy as it should be, it's only when going back I get problems. I can 
recall something about this being due to matching the zero-length 
character, but that does not help me much on getting it fixed. Ideas?

My version of emacs is 21.3.50.1, compiled on the mac from CVS.

Thanks!

Torbjørn