Problem with Natural RPC Server using NSC---P exit

Hello Fellows,
I don’t know if some one of you have experience using the NSC exit from the Java application. I am trying to use the NSC—P exit as a service calling from a Java application to make a kind of authentication process what I meant is a kind of a first level of secure access. The things is when I insert 3 times an invalid password the Natural RPC is going down.
I already read the description about the above exit mentioned and I understood that this exit terminate the session when the password is invalid. Could some one of you tell me what can I do to avoid the crashing Natural RPC Server or if you know another method to allow that first level of authentication.
The NSC—P exit is called by another Natural subprogram that specified the ESCAPE ROUTINE sentence. The flow of process is:

  1. Front end in Java to get userid & password
  2. Call a WSDL which invoke a web service on Natural for UNIX
  3. Execute a subprogram which invoke the NSC—P exit
    When this cycle is executed 3 times the Natural RPC Server crash

Thanks in advanced & Best Regards

FYI
I resolved that using the NSC API NSC—SP that API avoid the Natural session ended once the several attemps to log in failed

Regards