temp excluded from backup rman ORACLE Release 10.2.0.4.0

HI,
Using backup full rman, why tablespace TEMP is  not included  in full backup.


       TS# NAME          INCLUDED_IN_DATABASE_BACKUP
---------- ------------- ---------------------------
         0 SYSTEM        YES
         1 UNDO          YES
         2 SYSAUX        YES
         3 TEMP          NO

Error occurs at rman duplicate and i have to recreate Tablespace TEMP in the auxiliary database.

How can i modify NO by YES

Nothing is exclude in Rman

show exclude;

paramètres de configuration RMAN :
la configuration RMAN n'a pas de paramètres stockés, ni de paramètres par défaut


Thanks for any help.

Guy Encaoua