server lacks of instrumentation functions in CentOS

Hello when i connect to my database using PgAdmin· I get this message:
Server lacks of instrumentation functions.

I know That i need to run the admin81.sql script, but I don't know if my distribution has compiled postgresql to support that functions.
I installed the postgresql-contrib, but I don't know what is the module that I need to load, if there is one...?
can you tell me what to do?

 rpm -qil postgresql-contrib

Name        : postgresql-contrib           Relocations: (not relocatable)
Version     : 8.1.11                            Vendor: CentOS
Release     : 1.el5_1.1                     Build Date: Sat 12 Jan 2008 07:45:09 AM MST
Install Date: Sat 19 Jul 2008 01:03:04 PM MDT      Build Host: builder6
Group       : Applications/Databases        Source RPM: postgresql-8.1.11-1.el5_1.1.src.rpm
Size        : 1159682                          License: BSD
Signature   : DSA/SHA1, Sat 12 Jan 2008 08:50:36 PM MST, Key ID a8a447dce8562897
URL         : http://www.postgresql.org/
Summary     : Contributed source and binaries distributed with PostgreSQL
Description :
The postgresql-contrib package contains contributed packages that are
included in the PostgreSQL distribution.
/usr/bin/DBMirror.pl
/usr/bin/clean_pending.pl
/usr/bin/dbf2pg
/usr/bin/fti.pl
/usr/bin/oid2name
/usr/bin/pgbench
/usr/bin/vacuumlo
/usr/lib/pgsql/_int.so
/usr/lib/pgsql/autoinc.so
/usr/lib/pgsql/btree_gist.so
/usr/lib/pgsql/chkpass.so
/usr/lib/pgsql/cube.so
/usr/lib/pgsql/dblink.so
/usr/lib/pgsql/earthdistance.so
/usr/lib/pgsql/fti.so
/usr/lib/pgsql/fuzzystrmatch.so
/usr/lib/pgsql/insert_username.so
/usr/lib/pgsql/int_aggregate.so
/usr/lib/pgsql/isbn_issn.so
/usr/lib/pgsql/lo.so
/usr/lib/pgsql/ltree.so
/usr/lib/pgsql/moddatetime.so
/usr/lib/pgsql/pending.so
/usr/lib/pgsql/pg_buffercache.so
/usr/lib/pgsql/pg_trgm.so
/usr/lib/pgsql/pgcrypto.so
/usr/lib/pgsql/pgstattuple.so
/usr/lib/pgsql/pgxml.so
/usr/lib/pgsql/refint.so
/usr/lib/pgsql/seg.so
/usr/lib/pgsql/tablefunc.so
/usr/lib/pgsql/timetravel.so
/usr/lib/pgsql/tsearch2.so
/usr/lib/pgsql/user_locks.so
/usr/share/doc/postgresql-contrib-8.1.11
/usr/share/doc/postgresql-contrib-8.1.11/README.adddepend
/usr/share/doc/postgresql-contrib-8.1.11/README.apachelog
/usr/share/doc/postgresql-contrib-8.1.11/README.btree_gist
/usr/share/doc/postgresql-contrib-8.1.11/README.chkpass
/usr/share/doc/postgresql-contrib-8.1.11/README.cube
/usr/share/doc/postgresql-contrib-8.1.11/README.dbf2pg
/usr/share/doc/postgresql-contrib-8.1.11/README.dblink
/usr/share/doc/postgresql-contrib-8.1.11/README.dbmirror
/usr/share/doc/postgresql-contrib-8.1.11/README.earthdistance
/usr/share/doc/postgresql-contrib-8.1.11/README.fti
/usr/share/doc/postgresql-contrib-8.1.11/README.fuzzystrmatch
/usr/share/doc/postgresql-contrib-8.1.11/README.int_aggregate
/usr/share/doc/postgresql-contrib-8.1.11/README.intarray
/usr/share/doc/postgresql-contrib-8.1.11/README.isbn_issn
/usr/share/doc/postgresql-contrib-8.1.11/README.lo
/usr/share/doc/postgresql-contrib-8.1.11/README.ltree
/usr/share/doc/postgresql-contrib-8.1.11/README.mac
/usr/share/doc/postgresql-contrib-8.1.11/README.mpgsql
/usr/share/doc/postgresql-contrib-8.1.11/README.oid2name
/usr/share/doc/postgresql-contrib-8.1.11/README.ora2pg
/usr/share/doc/postgresql-contrib-8.1.11/README.pg_buffercache
/usr/share/doc/postgresql-contrib-8.1.11/README.pg_trgm
/usr/share/doc/postgresql-contrib-8.1.11/README.pgbench
/usr/share/doc/postgresql-contrib-8.1.11/README.pgbench_jis
/usr/share/doc/postgresql-contrib-8.1.11/README.pgcrypto
/usr/share/doc/postgresql-contrib-8.1.11/README.pgstattuple
/usr/share/doc/postgresql-contrib-8.1.11/README.pgstattuple.euc_jp
/usr/share/doc/postgresql-contrib-8.1.11/README.seg
/usr/share/doc/postgresql-contrib-8.1.11/README.soundex
/usr/share/doc/postgresql-contrib-8.1.11/README.spi
/usr/share/doc/postgresql-contrib-8.1.11/README.tablefunc
/usr/share/doc/postgresql-contrib-8.1.11/README.timetravel
/usr/share/doc/postgresql-contrib-8.1.11/README.tsearch2
/usr/share/doc/postgresql-contrib-8.1.11/README.user_locks
/usr/share/doc/postgresql-contrib-8.1.11/README.vacuumlo
/usr/share/doc/postgresql-contrib-8.1.11/README.xml2
/usr/share/doc/postgresql-contrib-8.1.11/autoinc.example
/usr/share/doc/postgresql-contrib-8.1.11/insert_username.example
/usr/share/doc/postgresql-contrib-8.1.11/moddatetime.example
/usr/share/doc/postgresql-contrib-8.1.11/refint.example
/usr/share/doc/postgresql-contrib-8.1.11/timetravel.example
/usr/share/pgsql/contrib
/usr/share/pgsql/contrib/AddTrigger.sql
/usr/share/pgsql/contrib/MirrorSetup.sql
/usr/share/pgsql/contrib/_int.sql
/usr/share/pgsql/contrib/autoinc.sql
/usr/share/pgsql/contrib/btree_gist.sql
/usr/share/pgsql/contrib/chkpass.sql
/usr/share/pgsql/contrib/cube.sql
/usr/share/pgsql/contrib/dblink.sql
/usr/share/pgsql/contrib/earthdistance.sql
/usr/share/pgsql/contrib/english.stop
/usr/share/pgsql/contrib/fti.sql
/usr/share/pgsql/contrib/fuzzystrmatch.sql
/usr/share/pgsql/contrib/insert_username.sql
/usr/share/pgsql/contrib/int_aggregate.sql
/usr/share/pgsql/contrib/isbn_issn.sql
/usr/share/pgsql/contrib/lo.sql
/usr/share/pgsql/contrib/lo_drop.sql
/usr/share/pgsql/contrib/lo_test.sql
/usr/share/pgsql/contrib/ltree.sql
/usr/share/pgsql/contrib/moddatetime.sql
/usr/share/pgsql/contrib/pg_buffercache.sql
/usr/share/pgsql/contrib/pg_trgm.sql
/usr/share/pgsql/contrib/pgcrypto.sql
/usr/share/pgsql/contrib/pgstattuple.sql
/usr/share/pgsql/contrib/pgxml.sql
/usr/share/pgsql/contrib/refint.sql
/usr/share/pgsql/contrib/russian.stop
/usr/share/pgsql/contrib/seg.sql
/usr/share/pgsql/contrib/slaveDatabase.conf
/usr/share/pgsql/contrib/tablefunc.sql
/usr/share/pgsql/contrib/timetravel.sql
/usr/share/pgsql/contrib/tsearch2.sql
/usr/share/pgsql/contrib/untsearch2.sql
/usr/share/pgsql/contrib/user_locks.sql