where is the locale set for each server instance?

Hi!

I'm pluggin ICU into PostgreSQL for unicode collation, since FreeBSD has no 
support for unicode collation. It works fine, but I cannot find out where 
to set the default locale for each backend instance. I want to use the 
LC_COLLATE used in initdb, now I've just hard wired it for my own needs. I 
tried backend/access/transam/xlog.c:ReadControlFile, but it is not 
sufficient.

in backend/main/main.c:/* * Set up locale information from environment.    Note that LC_CTYPE and * LC_COLLATE will be
overriddenlater from pg_control if we are in an * already-initialized database.
 

So, I'm trying to find out where LC_COLLATE is overridden. Any tips?

Thanks,
Palle