Users in pg_shadow

I have a cron script set up to run VACUUM ANALYZE on two databases that appear
to work fine except for a couple of messages that show up in the log:

FATAL 1: SetUserId: user 'newsltr' is not in 'pg_shadow'
FATAL 1: SetUserId: user 'wcgc_pg' is not in 'pg_shadow'

newsltr and wcgc_pg are the respective names of the databases, there are no
users with these names. This is on a postgresql-7.0.2 running on a Red Hat 6.2

I've seen no problems resulting from this but I would like to understand why.

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Scott Holmes http://www.pacificnet.net/~sholmes
sholmes(at)pacificnet(dot)net

Independent Programmer/Analyst Passport 4GL
PHP HTML Composer PostgreSQL Informix 4GL, SQL
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