Bug in pg_hba.conf or pg_basebackup concerning replication connections

All,

If I have the following line in pg_hba.conf:

host    replication     replication             all                     md5

pg_basebackup -x -v -P -h master1 -U replication -D $PGDATA
pg_basebackup: could not connect to server: FATAL:  no pg_hba.conf entry for replication connection from host
"216.121.61.233",user "replication"
 

But, if I change it to "all" users, replication succeeds:

host    replication     all             all                     md5

... even if the user "postgres" (the only other user in this test) is declared "with noreplication".

I can't figure out what's going wrong here; either HBA is broken and won't accept a replication line unless user is
"all",or pgbasebackup is doing something to test a connection as "postgres", even though no such connection attempt
showsup in the logs.
 

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com
San Francisco