[OS X Emacs] Aquamacs question: disable/rename backup files?

[Theodore Todorov]

Hello,

I discovered Aquamacs two weeks ago, and I find it very, very good.
It has become my main editor for development (C++ mostly).

There is just one small thing that is annoying, and that I hope an  
expert can answer off the top of her head (and yes, I looked in the  
help, the FAQ and the Wiki before asking):

aquamacs creates a backup file with the  
name ._OriginalName.originalExtension
in the same directory as the original file, for each file I edit.
This conflicts with the build system that I have to  use (and cannot  
change), which
simply compiles everything with a *.cxx extension in the src  
subdirectory of each package.
When it tries to compile the ._Whatever.cxx file I have a problem :-)

So the question is: how can I disable this backup mechanism, or change  
the name generation template so that the extension is modified? The  
"classical" emacs used to post-pend a tilde to the name, which worked  
fine...

       Thank you in advance,
            Teddy