File Descriptor error in RMAN

 

below is the log output of my first backup execution.  I know that disk space is not an issue, write permissions are not an issue.  Any idea why I would get a file descriptor error?  Please advise. 

Recovery Manager: Release 10.2.0.4.0 - Production on Mon Aug 24 12:19:48 2009

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connected to target database: DEVED (DBID=396662273)
connected to recovery catalog database

RMAN> run {execute script backup_db10g;}
2>
executing script: backup_db10g

executing script: archive_log_switch

sql statement: alter system switch logfile

Starting backup at 24-AUG-09
current log archived
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=523 devtype=DISK