Ubuntu – Change default shell when user not in /etc/passwd

Any ideas on how can I change the shell to fish?

$ sudo usermod -s /usr/bin/fish jaan
usermod: user 'jaan' does not exist in /etc/passwd
$ getent passwd $USER
jaan:x:15466:94:Jaan A:/home/jaan:/bin/zsh

Related questions: user does not exist in /etc/passwd when trying to change the default shell
Seems like it uses ldap.

$ cat /etc/nsswitch.conf
passwd:         compat ldap
group:          compat ldap
shadow:         compat ldap

# Having the NOTFOUND=return bit was breaking dns resolution on web1 and web2. But we probably
# don't want any of the mdns stuff so let's get rid of it all.
#hosts:          files mdns4_minimal [NOTFOUND=return] dns mdns4
hosts:          files dns

networks:       files

protocols:      db files
services:       db files
ethers:         db files
rpc:            db files

netgroup:       ldap
automount:      ldap

So I installed ldap relevant package.

$ chsh.ldap
LDAP password for jaan:
Enter the new value, or press ENTER for the default
  Login Shell [/bin/zsh]: /usr/bin/fish
Traceback (most recent call last):
  File "/usr/bin/chsh.ldap", line 69, in <module>
    constants.NSLCD_USERMOD_SHELL: shell,
  File "/usr/share/nslcd-utils/nslcd.py", line 128, in usermod
    assert con.get_response() == constants.NSLCD_RESULT_BEGIN
  File "/usr/share/nslcd-utils/nslcd.py", line 103, in get_response
    return self.read_int32()
  File "/usr/share/nslcd-utils/nslcd.py", line 71, in read_int32
    return _int32.unpack(self.read(_int32.size))[0]
struct.error: unpack requires a string argument of length 4
$ which fish
/usr/bin/fish
$ chsh.ldap
LDAP password for jaan:
Enter the new value, or press ENTER for the default
  Login Shell [/bin/zsh]: "/usr/bin/fish"
/usr/bin/chsh.ldap: "/usr/bin/fish" is an invalid shell
$ /usr/bin/fish
(standard_in) 1: syntax error
Welcome to fish, the friendly interactive shell