Where to set XDG_DATA_DIRS upon login?

[Chee Bin HOH <cbhoh mimos my>]

I need to set XDG_DATA_DIRS to <prefix>/share in order to run yelp to
view an online help, since the yelp is now using gnome-vfs for
identifying the location of the help file.


But it fails when I try to view any applet help by clicking on the help
item from any applet popup menu. The yelp prompts the error that "There
is no default action associated with this location.".


I set the environment variable XDG_DATA_DIRS in
<prefix>/etc/gdm/Xsession scripts, and my login session inherits it, but
it still does not help me to solve the problem (the yelp invoked by
applet through gnome_help_display function still fails).


I am able to view the online help of any applet by adding 'setenv
("XDG_DATA_DIRS", "<prefix>/share") inside the code just before the
calling egg_help_display_on_screen or gnome_help_display.


I can also view the applet help by calling yelp from a command line (my
shell inherit the XDG_DATA_DIRS from <prefix>/etc/gdm/Xsession), then
browse through it. but I just can not click on the help item from applet
popup menu.


Where should I set the env XDG_DATA_DIRS in order for the whole desktop
to function correctly?

- HOH