How to enable controlfile autobackup on in rman?

[oracle@wasiq ~]$ rman

Recovery Manager: Release 11.2.0.1.0 - Production on Fri Jan 10 21:07:53 2014

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RMAN> connect target /;

connected to target database: PROD (DBID=246965557)

RMAN> configure controlfile autobackup on;

using target database control file instead of recovery catalog
old RMAN configuration parameters:
CONFIGURE CONTROLFILE AUTOBACKUP ON;
new RMAN configuration parameters:
CONFIGURE CONTROLFILE AUTOBACKUP ON;
new RMAN configuration parameters are successfully stored

RMAN>