BUG #6068: automatic analyze runs endlessly

The following bug has been logged online:

Bug reference:      6068
Logged by:          Jeff Janes
Email address:      jeff.janes@gmail.com
PostgreSQL version: 9.1beta1
Operating system:   Linux
Description:        automatic analyze runs endlessly
Details:

Starting with commit b4b6923e03f4d29636a94f6f4cc2f5cf6298b8c8,
"Fix VACUUM so that it always updates pg_class.reltuples/relpages."

After running make installcheck, the tables regression.public.slow_emp4000
and regression.public.fast_emp4000 get analyzed once a minute even though
they have no activity.  None of the other installcheck tables, just those
two.

This has no direct negative effect that I know of, but it seems to be a
worrying symptom that pg_class or some related entity may not be getting
updated correctly.