Database Startup Failure: FATAL: could not read block 6 of relation 16390/16391/5153282: Success

Hi,

I have been asked to help recover a database that seems to have been corrupted after a power failure.

This is what we see when psql tries to start up:

[2009-11-10 10:39:17 EST] LOG: checkpoint record is at 41E/BF2D5DC0
[2009-11-10 10:39:17 EST] LOG: redo record is at 41E/BF008F28; undo record is at 0/0; shutdown FALSE
[2009-11-10 10:39:17 EST] LOG: next transaction ID: 0/143406361; next OID: 5219759
[2009-11-10 10:39:17 EST] LOG: next MultiXactId: 178368; next MultiXactOffset: 356812
[2009-11-10 10:39:17 EST] LOG: database system was not properly shut down; automatic recovery in progress
[2009-11-10 10:39:17 EST] LOG: redo starts at 41E/BF008F28
[2009-11-10 10:39:17 EST] WARNING: invalid page header in block 3 of relation "5166570"; zeroing out page
[2009-11-10 10:39:17 EST] CONTEXT: xlog redo newroot: rel 16390/16391/5166570; root 3 lev 1
[2009-11-10 10:39:17 EST] WARNING: invalid page header in block 84 of relation "5152721"; zeroing out page
[2009-11-10 10:39:17 EST] CONTEXT: xlog redo insert(init): rel 16390/16391/5152721; tid 84/1
... repeated a lot of times with various blocks and relations ...
[2009-11-10 10:39:17 EST] FATAL: could not read block 6 of relation 16390/16391/5153282: Success
[2009-11-10 10:39:17 EST] CONTEXT: xlog redo insert(init): rel 16390/16391/5153282; tid 6/1
[2009-11-10 10:39:17 EST] LOG: startup process (PID 14643) exited with exit code 1
[2009-11-10 10:39:17 EST] LOG: aborting startup due to startup process failure
[2009-11-10 10:39:17 EST] LOG: logger shutting down

Does anyone have any clues how we might recover this database?

Also what does it mean by "Success" in the FATAL message? Seems a strange fatal error...

Thanks in advance,
Regards // Mike