[AUCTeX] How to specify path to latex and gs?

[Deling Ren]

Hi all,

I have just compiled a carbon emacs and installed on a Mac. My latex  
and gs are both installed under /usr/local. But it seems that emacs  
(auctex) only searches for /usr/bin:/bin:/usr/sbin:/sbin (by checking  
$PATH under EShell mode). I wish to be able to do preview, so how do  
I tell auctex or emacs to search for /usr/local/bin as well (other  
than setting $PATH and starting /Applications/Emacs.app/Contents/ 
MacOS/Emacs from a shell)? Thanks.

Deling