title: Thrift API method 'authenticate' not found in WSO2 identity server 5.0
body: <p>I met a problem in WSO2 identity server 5.0 windows version.
  I download the version from wso2.com and unzip, start the server by running <code>$IS_HOME/bin/wso2server.bat</code>.
  Then I write a thrift java client, calling the authenticate API which is listed in </p>
  
  <pre><code>$IS_HOME/repository/components/plugins/org.wso2.carbon.identity.thrift.authentication_4.2.1.jar/authenticator.thrift
  </code></pre>
  
  <p>The calling failed, the error message was: </p>
  
  <pre><code>org.apache.thrift.TApplicationException: Invalid method name: 'authenticate'
              at org.apache.thrift.TApplicationException.read(TApplicationException.java:108)
              at org.wso2.carbon.identity.thrift.authentication.AuthenticatorService$Client.recv_authenticate(AuthenticatorService.java:95)
              at org.wso2.carbon.identity.thrift.authentication.AuthenticatorService$Client.authenticate(AuthenticatorService.java:77)
              at com.mine.client.WSO2Client.main(WSO2Client.java:40)
  </code></pre>
  
  <p>It seems that the server has received the request, but it can't find the 'authenticate' method.
  But the method is listed in authenticator.thrift.
  Is there anyone can help me?
  Thanks.</p>