Restore spfile or controlfile from autobackup beyond 366 days

The restore of spfile and control file from autobackup using maxdays option will fail if the maxdays specified is beyond 366 days:
RMAN> restore controlfile from autobackup maxseq 200 maxdays 500;
Starting restore at 21-oct-08 14:58using channel ORA_DISK_1
RMAN-00571: ===========================================================RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============RMAN-00571: ===========================================================RMAN-03002: failure of restore command at 10/21/2008 14:58:42RMAN-06494: MAXDAYS = 500 is out of range (1-366)
So how to restore spfile and control file from a backup taken more than 366 days ago? I found that when RMAN performs restore from autobackup file, it did not check the timestamp of the autobackup file but the timestamp that is stated in the autobackup file name. By changing the autobackup file name so that the timestamp is within the accepted range, it can find and read the autobackup file and restore the controlfile / spfile successfully.
Without the maxdays option, RMAN will only look for autobackup file with timestamp within the last 7 days. So if today is 22 Oct 08 and your autobackup file name in $ORACLE_HOME/dbs is “c-1154185322-20081012-01″, the “restore controlfile from autobackup” command will not be able to find or read the autobackup file.
Change it to “c-1154185322-20081021-01″ and RMAN will be able to restore the control file from autobackup with “restore controlfile from autobackup” command. I don’t have a controlfile autobackup created more than 366 days ago, but I think this trick can also address 366-maxdays limitation.