Unexpected VACUUM FULL failure

This is a bit disturbing:

*** ./expected/vacuum.out Sat Jul 20 00:58:14 2002
--- ./results/vacuum.out Wed Aug 8 20:16:45 2007
***************
*** 50,55 ****
--- 50,56 ----

DELETE FROM vactst WHERE i != 0;
VACUUM FULL vactst;
+ ERROR: HEAP_MOVED_OFF was expected
DELETE FROM vactst;
SELECT * FROM vactst;
i

======================================================================

This is today's CVS HEAD, plus some startup/shutdown logic changes in
postmaster.c that hardly seem like they could be related.

I couldn't reproduce it in a few tries. A reasonable guess is that
it's triggered by autovacuum deciding to vacuum the table sometime
before the VACUUM FULL starts. Anyone want to try to reproduce it?

regards, tom lane