migrating administrative pieces to new install

I have both a production machine and a test machine.
The production machine is running 6.5.2 and FreeBSD 3.0.
The test machine is running 6.5.3 and FreeBSD 3.4.

The idea is to migrate all databases from the prod. machine
to the test machine.  As soon as the test machine works properly
it will become the prod. machine and vice-versa.

All databases are read(select) only.  my pg_hba.conf looks like this:
    local all password passwd.

pg_dumpall fails.  I haven't found a way to supply a username
and password to the command.  The -u flag dosen't work.

pg_dump works but what databases/tables do I dump to get all my
username info.

Any hints for the hintless?

hal