Weblogic Session replication setup

Kind of a noob when it comes to weblogic, trying to implement session replication on WL with ATG.

1) Two servers in a WL cluster, drp1 and drp2

2) My deployed web-app has 'replicate_if_clustered' set in weblogic.xml.

3) With both servers running, I establish a session in my ATG webshop, adding something to basket.

4) Take down the server with the session.

The session I can see through the monitoring page of the application, is migrated to the remaining server.  So far, so good. I can access my site, I still have my basket.

5) Restart my stopped server;

6) After a brief pause, I take down the server with the session