ORA-27069 during RMAN backup

  Hi,

we are getting the following error during RMAN backup. The RMAN backup ran fine day before yesterday but yesterday gave us the following error
Its 10.2.0.4 on HP Open VMS 8.x
can you please help?


channel ORA_DISK_1: starting piece 1 at 05-MAY-10
channel ORA_DISK_1: finished piece 1 at 05-MAY-10
piece handle=dkb3:[rmanbackup]0vlcumr9_1_1. tag=TAG20100505T210025 comment=NONE
channel ORA_DISK_1: starting piece 2 at 05-MAY-10
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup plus archivelog command at 05/05/2010 21:01:45
ORA-19502: write error on file "dkb3:[rmanbackup]0vlcumr9_2_1.", blockno 24449 (
blocksize=8192)
ORA-27069: attempt to do I/O beyond the range of the file