BUG #6199: Can't install datatype hstore

The following bug has been logged online:

Bug reference: 6199
Logged by: Hadmut
Email address: hadmut(at)danisch(dot)de
PostgreSQL version: 9.1 rc1
Operating system: Ubuntu Oneiric
Description: Can't install datatype hstore
Details:

Hi,

I'd like to run a database application which requires datatype hstore.

But when trying something like

psql -f /usr/share/postgresql/9.1/extension/hstore--1.0.sql

I get error messages like

psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:8: NOTICE: return
type hstore is only a shell
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:8: ERROR: could
not access file "MODULE_PATHNAME": Datei oder Verzeichnis nicht gefunden
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:13: NOTICE:
argument type hstore is only a shell
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:13: ERROR: could
not access file "MODULE_PATHNAME": Datei oder Verzeichnis nicht gefunden
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:18: NOTICE: return
type hstore is only a shell
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:18: ERROR: could
not access file "MODULE_PATHNAME": Datei oder Verzeichnis nicht gefunden
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:23: NOTICE:
argument type hstore is only a shell
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:23: ERROR: could
not access file "MODULE_PATHNAME": Datei oder Verzeichnis nicht gefunden
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:32: ERROR:
function hstore_in(cstring) does not exist
psql:/usr/share/postgresql/9.1/extension/hstore--1.0.sql:37: NOTICE:
argument type hstore is only a shell

...

regards