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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703

Description of problem:
In RH 7.3, underscores were allowed in usernames.  However, when I upgraded the
system, underscores were no longer supported which caused problems with edititng
the user b/c redhat-config-users would not accept the underscores in the
usernames.  Using underscores in usernames is not unheard of nor is it advised
against.

Allowing underscores in usernames ensures backwards compatability with older
versions of RH, ensures compatibility with other Linux distros on the same box,
if they share users and /home directories

Version-Release number of selected component (if applicable):
redhat-config-users-1.1.10-1

How reproducible:
Always

Steps to Reproduce:
1.Run redhat-config-users
2.Add or Edit existing user
3.Use underscore in the username
    

Actual Results:  redhat-config-users does not accept underscores in the usernames

Expected Results:  redhat-config-users should accept underscores in the usernames

Additional info: