Corruption Problem

Hi Guys
I Have a funny problem
in my alert log i got the following errors for about 15mins
***

Corrupt block relative dba: 0x0a877fd8 (file 42, block 491480) Bad header found during buffer read
Data in bad block -
 type: 6 format: 2 rdba: 0x0b801ea2
 last change scn: 0x0000.17a9d140 seq: 0x1 flg: 0x02  consistency value in tail: 0xd1400601
 check value in block header: 0x0, block checksum disabled  spare1: 0x0, spare2: 0x0, spare3: 0x0
***

now i found which table was at that block analyzed that table with cascade, no errors were reported i then didi a full table scan, no errors, then i did an export of that table no errors were reported ???????
what could cause this?
I'm running on HP-UX 64 bit
and i did apply the 8.1.7.2.1 patch yesterday, could it be related? all Oracle tells me is to keep an eye it. I was hoping someone could give me a little more insight into this or if you have experienced any similiar kind of problems with corruption that wasn't there

Thanks for any Help

David Hill
DBA
LeChateau

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Author: david hill
  INET: david.hill_at_lechateau.ca

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