cd /usr/local/src
lynx --source http://www.tcu-inc.com/perl5.6.1.tgz > perl-5.6.1.tgz
tar -zxvf perl-5.6.1.tgz
cd perl-5.6.1
rm -f config.sh Policy.sh
sh Configure
Change the default prefix to "/usr" instead of "/usr/local". Also, when it asks the question "Build a
shared libperl.so (y/n) [n] ", answer y. Press enter for any other question.
make
make install
Then I downloaded and install postgresql.
./configure --prefix=/usr/local/pg711 --with-perl --with-tcl --with-CXX --with-python --enable-odbc
cd /usr/local/src/postgresql-7.1.1/src/interfaces/perl5
perl Makefile.PL
make
make install
ln -s /usr/lib/perl5/5.6.1/i686-linux/CORE/libperl.so \ /usr/local/pg711/lib/libperl.so
su -c 'createlang plperl template1' postgres
Then I started psql as postgres, and ran teh create language command.