Even there is a possibility to create loginname with a dot (ie: milan.kerslager) in RHEL3 and RHEL4 with standard shadow-utils (see bug #159034 for fixing this up in RHEL3), there is no possibility to create such user in system-config-users. Please apply this one-line patch. Thank you. Possibly apply to RHEL3 too.
Created attachment 135039 [details] Allow dot in username
*** This bug has been marked as a duplicate of 159035 ***