Currently when the user changes the password from Nomad Web via "Change Password" menu then it can successfully change the password in the ID Vault. However if there is a Security Policy set in Domino to sync the ID file password with internet password via Security Policy > Settings > Password Management > Update Internet Password When Notes Client Password Changes: Yes, then it fails to update the Internet password of the user.
This is because, when the ID file password is changed via Notes Client then it also submits an AdminP request "Change HTTP password in Domino directory" in admin4.nsf which allows to update the Internet password of the user. However such AdminP request is not submitted when the ID file password is changed via Nomad.
Due to this, users can't sync their ID file password and internet password and thus it creates a confusion in users as they need to use 2 different passwords.
So there is a feature request to add support in Nomad for submitting an AdminP request to update the internet password just like how the Notes Client does it.
This Enhancement Request is submitted for Nomad 1.0.13 version.
Yes, password change in ID files should always be the same. No matter which client is used.