Data corruption question

Below is a trace file entry that I have noticed today and has repeated itself with identical data about 6 times over a 24 hour period leaving an open entry at the end of the trace file that has no timestamp. I can identify the fact that it picks out a corupt data block in file 6 [Index datafile]. There have been no unusual problems reported by the users and I have carried out a recovery (onto a test machine using the hot backup taken over the last 24hours and rolled forward through the time the errors were shown with out problem
What I would like is any assistance regarding the possible severity of the entry and what if anything I can do to rectify it. Sorry if I seem a bit of a numpty only I have not encountered anything like this before and as we have no Oracle support cannot address it to them.

Thanks for any help or assurance you can give me. Mick

Dump file *******\RDBMS73\trace\ORA00273.TRC Tue Apr 10 12:34:04 2001
ORACLE V7.3.3.0.0 - Production Release vsnsta=0 vsnsql=b vsnxtr=3
Windows NT V4.0, OS V5.101, CPU type 586 Oracle7 Workgroup Server Release 7.3.3.0.0 - Production Release With the distributed option
PL/SQL Release 2.3.3.0.0 - Production
Windows NT V4.0, OS V5.101, CPU type 586 Instance name: pims
Redo thread mounted by this instance: 1
Oracle process number: 35
pid: 111
Tue Apr 10 12:34:04 2001
*** SESSION ID:(36.10) 2001.04.10.12.34.04.085
***

Corrupt block dba: 0x06018cab file=6. blocknum=101547. found during buffer read
on disk type:6. ver:0. dba: 0x009b008b inc:0x00020000 seq:0xd44700d5 incseq:0x0f0f0f0f
Reread of block=6018cab file=6. blocknum=101547. found same corupted data Tue Apr 10 13:25:48 2001
***

Corrupt block dba: 0x06018cab file=6. blocknum=101547. found during buffer read
on disk type:6. ver:0. dba: 0x009b008b inc:0x00020000 seq:0xd44700d5 incseq:0x0f0f0f0f
Reread of block=6018cab file=6. blocknum=101547. found same corupted data

This entry has recurred on over 6 occasions since the initial one. Received on Wed Apr 11 2001 - 16:51:23 CDT