Using different clients to change password result in different stored password's form

[kadafax <kadafax@gmail.com>]

Hi list,
as I don't know if this behavior comes from my slapd itself, I'm not
giving too much details on it. Here is what's happening:
in slapd.conf I have: 'password-hash {SSHA}' so I'm expecting that each
password attribute change results in a new SSHA hashed password.
Our users can change their password on several ways which all result in 
different stored password'hashes (cleartext (!), SHA, but not SSHA). 
Does the hashing type is specified on the client's side and not enforced 
by the directory? Can someone give me some pointers for doc explaining 
how password's change mechanism works in openldap?

kfx