bibtex-mode and "format region" incredibly slow

[John Owens <jowens@ece.ucdavis.edu>]

I use BibTeX mode for my bibliographies. I use it on both NT emacs
(the 21.3 release) and the CVS build for OS X. I have ~150 entries in
a BibTeX file and want to format and sort them.

Calling "format region" on the whole file via the BibTeX menu is
*incredibly* slow on OS X emacs, but very quick on NT emacs. I would
estimate on NT it's a few seconds and works fine. I've never actually
waited for a OS X "format region" to finish on the Mac but it's at
least several minutes. Nothing else I do on OS X emacs is even close
to this discrepancy in performance. In addition, emacs is accounting
for ~70% of my CPU utilization while it attemps to format the region. 

When I hit C-g, it leaves my BibTeX buffer with thousands of blank
lines in it (and on this test, crashed immediately afterwards).

It appears that I'm using straight bibtex mode (locate-library bibtex
returns /usr/local/share/emacs/21.3.50/lisp/textmodes/bibtex.elc).

Ideas?

JDO