BUG #8236: wal_sync_method open_datasync unavailable

The following bug has been logged on the website:

Bug reference:      8236
Logged by:          Ivan
Email address:      akifo@akifo.net
PostgreSQL version: 8.4.4
Operating system:   CEntOS 5.4
Description:

Sync method ":open_datasync" daclared as supported (
http://www.postgresql.org/docs/8.4/static/runtime-config-wal.html )


But after changing this parameter I've got the following error:


FATAL:  invalid value for parameter "wal_sync_method": "open_datasync"
HINT:  Available values: fsync, fdatasync, open_sync.