Problems trying to get currency separator correct for CAD

[bunk3m]

I'm using Gnucash 2.4.7 on OSX 10.5.8.

I've been searching but not found how to change the "," (comma) to "."
(decimal) to separate the dollars and cents.  This is not the standard
for Canada (English speaking Canada anyway.  Not sure what our
Francophone cousins use...)

I set locale "Canadian Dollars" "CAD" in the Gnucash preferences.  The
default locale in Preferences is correct ie. CAD (Canadian Dollar)

My number settings in System Preferences is $1,234.56.

All other applications including Quicken, SeeFinance, Libreoffice, Excel
etc. use the correct currency separator.  Gnucash isn't picking it up
properly.

In the FAQ it says to do the following command to customize: "defaults
write -app Gnucash AppleLocale = "en_US at currency=CAD" "

This command should actually be:

    defaults write -app /Applications/Gnucash/Gnucash.app
AppleLocale="en_US at currency=CAD"

But I get an error:
   2011-07-20 13:42:44.553 defaults[4877:10b]
   Rep argument is not a dictionary
   Defaults have not been changed.

I have no idea what this is supposed to mean and would appreciate some
guidance on how to get the "," currency separator to ".".

Thanks in advance.
B