Problem with pg_log file corrupted

Hi,
I think the pg_log file of my postgreSQL is corrupted after a power
failure.
I can;t access to tables in my database now.
The error message appear when I tried to list all tables is as below :
" cannot flush block 8 of pg_log to stable store "
Anybody know how can I restore back the pg_log file.
Thanks.

Emmanuel Wong