[imp] poppassd cannot change passwd by user, but the root user can do.

[Pradit Wattanasuwan]

Dear All,
 I have some questions about poppassd to ask you. Why the user(not the root 
user) cannot change passwd by them self, but the root user can do?
I showed the content that I did on below.
Error: 500 Username and old password don't match.

If you have idea, please let's me know.
Thanks,
Pok

$ id
uid=1001(cri001) gid=2000(temp)
$ ./poppassd
200 poppassd here; who are you?
user cri001
200 your current password please.
pass cri001
500 Username and old password don't match.
$ exit
# ./poppassd
200 poppassd here; who are you?
user cri001
200 your current password please.
pass cri001
200 your new password please.
newpass abc123
200 Password changed. Have a nice day.
quit
200 Bye-Bye.
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