6.5.2 vacuum NOTICE messages

Hi,

I have a cron job which vaccuming database every hour
(say for testing purposes) and sometimes I get following messages:

NOTICE:  Index hits_pkey: NUMBER OF INDEX' TUPLES (10003) IS NOT THE SAME AS 
HEAP' (10004)
NOTICE:  Index hits_pkey: NUMBER OF INDEX' TUPLES (10003) IS NOT THE SAME AS 
HEAP' (10004)

This happens on Linux 2.0.37, postgresql 6.5.2

What does it means ? Why it's happens not every time script runs ?
What's the best way to get rid off this problem except dump/reload ?

The script is here:

/usr/local/pgsql/bin/psql -tq discovery <vacuum_hits.sql

vacuum_hits.sql:

begin work;
vacuum analyze hits(msg_id);
drop index hits_pkey;
create unique index hits_pkey on hits(msg_id);
end work;

Regards,
    Oleg




_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83