When logging in from unix98 ptys, pam_securetty looks in /etc/securetty to see if that terminal is allowed. The module looks at the part of the device after the last '/' to match against the entry in /dev. If users add 'pts/1' to /etc/securetty this will not work. The user must add '1' to /etc/securetty as pam_securetty looks at only the part after the last '/'.
This issue has been forwarded to a developer for further action.
Fixed in the current package from rawhide