Not connecting to the postgresql server

I need help with why my server is having issues. There is nothing in the
logs showing any errors on startup. This is the command and error I get
from a remote server when testing.

psql -h 172.16.36.231 -p 9999 -l

psql: ERROR: MD5 authentication is unsupported in replication,
master-slave and parallel modes.
HINT: check pg_hba.conf

This is from the pg_hba file on my master pgpool server.

host all postgres <xxx.xxx.xxx.xxx/xx> trust

The ip address covers the entire network at the moment.

Looking through the help documents through out the internet not really
finding guidance. running version 3.3.3-1

Thanks,
Eric Speake
Web Systems Administrator
O'Reilly Auto Parts
(417) 862-2674 Ext. 1975

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