Can not register new user in RAM

We normally use following code to register user in RAM by call RAM client API:
     user.setName("test");
     user.setEmail("test@us.ibm.com");
     session.put(user, new RAMStatusMonitor());

In most of our RAM environment it is no problem, but in one server the above codes run successfully but not take effect in the end.
I checked RAM DB and found:
1) This user record exist in  RAM DB USERID table.
2) The problem is in this environment the attribute "uid_status" is 1 but in other environment is 0.

I not found any place to set RAM user status, after I manually change this status to 1, then user allow to visit RAM, otherwise during user login he always redirect to "Register" page.
How we set RAM configuration to prevent the user register for new user?
Thanks.