Emacs quitting on Control-G when committing to mercurial

[Roy Smith]

I'm running:

GNU Emacs 22.1.1
OSX-10.6.8
Mercurial Distributed SCM (version 1.6.4+20101001)

If I do "hg commit", emacs is run as I would expect, but if I type a Control-G, 
I get an "interrupted!" message, and emacs quits (leaving the terminal modes 
unrestored).

Running ps shows that the command being executed is:

    emacs -nw 
/var/folders/p5/p5Gj6NRtF-yAXT+X0YVgJU+++TM/-Tmp-/hg-editor-wQEeGG.txt

If I run that manually, I get normal operation.  I assume there's something 
funky about the environment in which emacs is being executed, but I can't 
figure out what that might be.  Any ideas?

It doesn't seem to be related to the buffer; I get the same problem in other 
buffers.  M-X make command summary shows, for both the normal and broken 
situations:

    C-g             keyboard-quit            <JISX0208>     self-insert-command

--
Roy Smith
roy@panix.com