Post Installation problem

Hi all,

I have installed PostgreSQL the following way:

./configure --prefix=/opt/postgresql --enable-locale --enable-multibyte
--enable-unicode-conversion --with-perl --with-CXX --with-gnu-ld
--enable-syslog
make
make install

At the post installation I get the following problem:
Success. You can now start the database server using:

/opt/postgresql/bin/postmaster -D /opt/postgresql/data
or
/opt/postgresql/bin/pg_ctl -D /opt/postgresql/data -l logfile start

wuppy:~$ /opt/postgresql/bin/pg_ctl -D /opt/postgresql/data -l logfile
start
postmaster successfully started
wuppy:~$ createdb test
/opt/postgresql/bin/psql: show: command not found
createdb: database creation failed

In the documentation I can't find this error. And since I am new to
databases I am looking for someone who can point me in the right
direction, to solve this problem.

Any help is very appreciated.

Greetings,

Dennis Leeuw