Setting default permissions under gnome

[Jack Dodds <brmdamon aci on ca>]

I'm using Debian Sarge.

At present, while using Gnome, applications typically create files with 
permissions rw-r--r--.

I want to change this so that files are craeted with permissions rw-r-----.

That is, I want umask to be 0027, not 0022.

I have changed the default umask in /etc/login.defs and /etc/profile and 
my own .bash/profile.

This works for non-graphical sessions, but gnome-terminal continues to 
show umask = 0022, and applications continue to create files with 
permissions rw-r--r--.

I've searched various documentations and also greped files in /etc for 
umaak, and have found nothing.

What is setting the overall default umask to 0022 and how can I change it?