psql 8.0.0 rc5 parser error on \dt?

I built 8.0.0rc5 on FreeBSD 4.8. It built with no errors. I then
tried psql using another host running postgresql 7.1.3 and I get the
goofy error message shown below. Other backslash commands seem to work
(ie. \? \e \q).

$ psql -h host-running-7.1.3 test
Welcome to psql 8.0.0rc5, the PostgreSQL interactive terminal.

Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit

test=> \dt
ERROR: parser: parse error at or near "."
test=> \q
$

Just to see if there might be something funny with the flex generated
parser, I ran flex against psqlscan.l; the output was identical to the
original psqlscan.c.

I built postgresql with:

$ pg_config --configure
'--with-template=freebsd' '--with-pam' '--with-openssl' 'CFLAGS= ' 'CPPFLAGS= ' 'LDFLAGS=-L/usr/local/lib'

I have not installed postgresql previously on this system, so it cannot
be picking up anything from a previous install.

A question: where would I go to check if this problem has already
been reported?

Thanks.

Dave Bodenstab