Unrecognized variable client_encoding

I had noticed in a previous post the following information:

> NOTICE:  Unrecognized variable client_encoding

>It means you're running a MULTIBYTE-enabled psql (or more specifically
>libpq) against a non-MULTIBYTE server.  Perhaps you are invoking a copy
>of libpq from an older installation that was compiled with different
>configure options.

>The notice is harmless enough, but you may want to get your client and
>server into sync...


I'm running into the same error message & I'm not sure how I got my client
and server out of sync.

 I did an install of 7.0.3 on a RedHat Linux 6.2 box that has had all
previous versions of postgreSQL removed.
When I configured it, I did ./configure --with-perl --with-odbc
--enable-syslog --enable-debug --enable-cassert  . Since my database will
not need any multibyte characters,  I specifically did not use
--enable-multibyte. My regression test went great, and after I  edited the
system's sysctl.conf to set the shmall and shmmax, postmaster started up
like a trooper. I then did the quickie test of

$ createdb
$ psql
postgres=>SELECT datetime 'now';
postgres=>\q
$ destroydb

When I did the create and the destroy, I got the "Unrecognized variable
client_encoding" notice, so obviously I'm out of sync.  The question is how
did I get that way?

I also tried recompiling with the multibyte enabled.  This time I got an
error along the lines of : multibyte is not enabled.
Your installation may not have been successful.

Any suggestions?

Thanks.