B-tree crash recovery error in 8.3 beta 2

Hi,

I've found that B-tree crash recovery in 8.3 beta2 could make some
tuples invisible through B-tree. They're visible if we read using but
Seq-Scan. This happens in 8.3 beta2, but not in 8.2.4. Here's how it
happens.

1. Create b-tree for a text type column.
2. Make B-tree three-story, that is, root-intermediate-leaf. Insert
tuples sufficient to construct such B-tree.
3. No checkpoint should occur during 2.
4. Kill postmaster.
5. Restart postmaster. Crash recovery will be done.
6. Tuples with column values less than HIKEY becomes invisible through
Idx-scan, still visible through Seq-scan.

From the dump of B-tree, it seems that HIKEY value is cleared (only
tuple header is left). No problem was found in the case of integer or
numeric type columns.

Attached is the shell script, postgresql.conf (almost the default one)
to reproduce the problem, and the log of the problem reproduction.

--
Koichi Suzuki