BUG #4601: Data saving and opening problem

The following bug has been logged online:

Bug reference:      4601
Logged by:          V KUMAR
Email address:      kumarv@nic.in
PostgreSQL version: 8.1.4
Operating system:   linux
Description:        Data saving and opening problem
Details:

we are experiencing the following error intermittenly in saving and opening
the data.

  While saving:

      Database error:     Error in saving the FMB MAP(Tippan). An I/O error
occured  while  sending to the backend.


  While opening:

             Database error: Error opening FMB Map of 2808060345. An I/O
error occured   while sending to the backend.


If we delete the record '2808060345', it shows error in another record and
goes on. The database was working perfectly earlier.