If you use wsdl and java, here is how I do it:
private static void updateUser(String userid,String dn, String profilename)
{



UpdateUserReq updateUserReq= new UpdateUserReq();
UpdateUserReqPrimaryExtension primaryExtension=new UpdateUserReqPrimaryExtension();
primaryExtension.setPattern(dn);
primaryExtension.setRoutePartitionName("PT-System");
updateUserReq.setPrimaryExtension(primaryExtension);
UpdateUserReqPhoneProfiles phoneProfiles=new UpdateUserReqPhoneProfiles();
String[] profileName=new String[1];
profileName[0]=profilename;
phoneProfiles.setProfileName(profileName);
updateUserReq.setPhoneProfiles(phoneProfiles);
updateUserReq.setUserid(userid);


try {

StandardResponse r = stub.updateUser(updateUserReq);
System.out.println ("Result: " + r.get_return());

} catch (Exception err) {
System.out.println("Fault: "+err.getMessage());


}
}