Could not locate a valid checkpoint record

Hi all

I tried to start a PostgresSQL instance this morning, but it failed. So
I checked the log:

2010-06-24 09:00:28 LOG: database system was shut down at 2010-06-24
08:13:58

2010-06-24 09:00:28 LOG: record with zero length at 9/E0E9D200

2010-06-24 09:00:28 LOG: invalid primary checkpoint record

2010-06-24 09:00:28 LOG: record with zero length at 9/E0E9D1B0

2010-06-24 09:00:28 LOG: invalid secondary checkpoint record

2010-06-24 09:00:28 PANIC: could not locate a valid checkpoint record

This application has requested the Runtime to terminate it in an unusual
way.

Please contact the application's support team for more information.

2010-06-24 09:00:28 LOG: startup process (PID 1644) exited with exit code 3

2010-06-24 09:00:28 LOG: aborting startup due to startup process failure

2010-06-24 09:00:29 LOG: logger shutting down

I know this error requires you to restore from backup, but,
unfortunatelly, we have no backup.
There is any way I can recover the data?

Thanks

Norberto