11g: how to get Client Result Cache to work?

I am trying to get Client Result Cache to work in Oracle 11g database. This feature is described in OCI Programmer's Guide, pages 10-22 - 10-27.

1. Parameter CLIENT_RESULT_CACHE_SIZE has been set to 1000000 and database restarted. I can see new value in V$PARAMETER.
2. Parameter RESULT_CACHE_MODE has been set to FORCE.

I am definitely getting results cached on the server: I can see it in V $RESULT_CACHE_* views and performance of large table scans is subsecond.  However, view CLIENT_RESULT_CACHE_STATS$ is empty, so I assume that
results do not get cached on the client. Any idea what is missing?

How the teste were done:
- Using SQL*Plus running on the same server as database. I tried
Bequeath
connections and connections though listener (listener is also 11g).
- Large table is created (no indexes)

• Full table scan is performed using SELECT COUNT(*) so result set consists of one row.
• There is no sqlnet.ora