passwd command works incorrectly when using -l and -u
options.
-u option do not recover hash properly and cause
impossibility for the
target user to log in. Example:

iser test.
his hash from /etc/shadow is CodMKO/mkdJ2I
now root enters #passwd -l test
now in /etc/shadow tests's hash is !CodMKO/mkdJ2I
That's ok. Now trying #passwd -u test
passwd writes Success. Opening /etc/shadow and tests's hash
is:
CodMKO/mkdJ2I~E^U@^P
... ;-(
now user test will never be able to log in.... and root
should munaully
edit /etc/shadow to correct the problem.

Thanks, Dmitri