Unable to createlang

I am having a problem trying to create a language in a new install of Postgres
- I have installed postgres 9.1 on a minimal (i.e. no GUI) CentOS 6.2 system.
- Psql is running and I am able to connect to the database from pgAdmin running on a Windows box.
- Postgres was installed in /opt/postgres
- The data was placed in /var/postgres/data.

I am migrating a database from an 8.4 system to the new system. I am trying to add the plperl and plperlu languages, which are used in the 8.4 system.

The command I am using is:

createlang -U postgres plperl hf-hvpa

The message I get back is:

createlang: language installation failed: ERROR: could not load library "/opt/postgres/lib/postgresql/plperl.so": libperl.so: cannot open shared object file: No such file or directory

I am doing this as the root user, but I have also tried it using my login and as the postgres user. The plperl.so file is in the indicated directory, but I am not sure what the reference to libperl.so means. Is that a separate file I need to download?

I am fairy new to both Linux and Postgres, however I have successfully installed Postgres on a Windows systems.

Sincerely appreciate any help.

Tom Harkaway