RMAN: full backup error after incomplete RECOVERY

Hi all,

After testing a INCOMPLETELY RECOVERY of the database, I took a full backup right away then I have an errors as below:

Starting backup at 27-FEB-06
current log archived
using channel ORA_DISK_1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 02/27/2006 16:17:55
ORA-06550: line 1, column 109:
PLS-00553: character set name is not recognized
ORA-06550: line 0, column 0:
PL/SQL: Compilation unit analysis terminated



But if I shutdown this databae right after imcomplete RECOVERY and run the full backup then everything worked fine.

Why am I getting the errors, I don't think we have to shutdown the DB after incomplete recovery, do we??? Is there a glitch somewhere on my backup/recovery strategy????

thanks all.