The Common Directory Service APIs are available in IS that may be invoked from a java service to modify the password of a MWS user from the system directory service. If your users are in LDAP/AD/Database or some other external source then the password is readonly in MWS and changing the passwords would require custom code that knows how to communicate with the backend user store to modify a password.
On the other hand, MWS system users can change their own password within MWS using their own profile UI.
#webMethods#webMethods-BPMS#MWS-CAF-Task-Engine