Help ! Service fails to start

Dear Friends,

I really need advise for my problem, 7 days ago Postgresql service
fails to start and i have no backup ! (OS: Windows XP Pro)

I tried to start the service manually from control panel, it started
for about 3 second, after that stop again.

This is the error in log files :

2009-11-02 10:13:29 LOG: database system was interrupted while in
recovery at 2009-10-30 06:33:49 Malay Peninsula Standard Time
2009-11-02 10:13:29 HINT: This probably means that some data is
corrupted and you will have to use the last backup for recovery.
2009-11-02 10:13:29 LOG: checkpoint record is at 3/DA21E418
2009-11-02 10:13:29 LOG: redo record is at 3/DA21E418; undo record is
at 0/0; shutdown FALSE
2009-11-02 10:13:29 LOG: next transaction ID: 0/139856773; next OID:
28846
2009-11-02 10:13:29 LOG: next MultiXactId: 4; next MultiXactOffset: 7
2009-11-02 10:13:29 LOG: database system was not properly shut down;
automatic recovery in progress
2009-11-02 10:13:29 LOG: redo starts at 3/DA21E468
2009-11-02 10:13:35 FATAL: could not access status of transaction
139856778
2009-11-02 10:13:35 DETAIL: Could not read from file "pg_clog/0085"
at offset 98304: Permission denied.
2009-11-02 10:13:35 CONTEXT: xlog redo commit: 2009-10-20 17:20:42
2009-11-02 10:13:38 LOG: startup process (PID 1284) exited with exit
code 1
2009-11-02 10:13:38 LOG: aborting startup due to startup process
failure
2009-11-02 10:13:38 LOG: logger shutting down

It seems that i still have chance to redo or undo the record that
caused this error. But how to do that ? How to find that file ?
Postgresql data folder only contain numbered filename.

Thank you for any help.