WindowsSync password not synced when changed via ldapmodify

I came across this problem today.

When changing passwords from the Fedora console, it works and syncs 
across to AD.
When changing passwords using 'passwd', it does not sync until 
pam_password is changed to ssha in ldap.conf. Then it syncs fine.
When changing passwords via ldapmodify in SSHA form, passwords do not sync.

Has anyone experienced this behavior?

Does anyone have a solution?

I'd like to change passwords via a PHP web interface.

Thanks,
Jeff