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User-Agent: Mozilla/4.78 [en] (X11; U; Linux 2.4.9-34smp i686)

Description of problem:
/etc/profile.d/lang.csh contains the erroneous syntax: 
  setenv LANG=$GDM_LANG
which makes a mess for csh or tcsh. I upgraded from RH6.2 to RH7.2. Under tcsh I
have the environment variable "LANG=en_US" (really! That is the name, not the
name and value!) and it is set to null, as well as the variable "LANG" set to
"en_US". When all this passes into sh, I have only the environment variable
"LANG" but the value is "en_US=". This is an illegal locale and causes much
grief (Perl, Netscape, Emacs, etc.) Correcting the bogus line in lang.csh fixes
the problem entirely. Interestingly, on another machine with a clean
installation of RH7.2, the GDM_LANG variable is not used, so the problem does
not surface.

This could plausibly be the cause for bug 55663.  Maybe?

How reproducible:
Always

Steps to Reproduce:
1.If $GDM_LANG is set before sourcing /etc/profile.d/lang.csh
2.Pass from tcsh to sh
3.check value of $LANG