BUG #6386: PITR never find a consistent recovery point

The following bug has been logged on the website:

Bug reference: 6386
Logged by: Max Kunz
Email address: max(dot)kunz(at)atip(dot)de
PostgreSQL version: 9.0.0
Operating system: CentOs
Description:

Hello,

i've got a Problem during PITR.

The Systems stops always with fatal error:

FATAL: requested recovery stop point is before consistent recovery point.

One system is configured as standby, performing stream and WAL replication.
Another system is running in primary mode.
I have verified that the standby system performed the basebackup
successfully. Hours later I did like to perform a PITR. I use a target_time
which is one hour later than stop_basebackup_time. In spite of that fact,
i've got the error message.

I'm able to start this server in primary mode, but it's not possible to
perform a PITR one minute ago.

Do you have any idea why the system don't find a consistent point for PITR
but for normal startup in primary mode?

kind regards Max