Update User Password via Web Services

Question

Hello. I am attempting to update the password for a user via the Rights Management web services, https://{mydomain}/soap/services/RightsManagementService?wsdl&lc_version=9.0.1, using .NET 4.0 (C#).
Below is the function I have written. When I execute the code it always returns false. I have searched the documentation and forumns but have not found anything. Can someone provide any ideas on how I can successfully update a users password in LiveCycle via the exposed web services?
public bool UpdateUserPassword(string userName, string password)
            bool result = false;
            WebServices.RightsManagement.UserImpl user = new WebServices.RightsManagement.UserImpl();
            user.userid = userName;
            user.canonicalName = userName;
            user.domainName = DefaultPolicySets.DefaultDomain;
            user.principalType = "USER";
            user.local = true;
            user.locked = false;
            user.disabled = false;
            user.system = false;
            Console.WriteLine(this.rmSvc.resetExternalUserPassword(user, password));
            return result;

Answer 1

The answer to this question was to use another function exposed by the Directory Management Web services, {domain}/soap/services/DirectoryManagerService?WSDL&lc_version=9.0.1.
The function in question is called updateLocalUser().
You can find more information here, http://help.adobe.com/en_US/livecycle/9.0/programLC/javadoc/com/adobe/idp/um/api/Directory Manager.html#updateLocalUser%28com.adobe.idp.um.api.infomodel.User,%20java.lang.String%29.