pg_dump errors

Hi all;

I'm seeing these errors when running a pg_dump of the postgres database:

Running: [pg_dump --schema-only postgres > postgres.ddl]
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR: could not find hash function for
hash operator 33639
pg_dump: The command was: SELECT a.attnum, a.attname, a.atttypmod,
a.attstattarget, a.attstorage, t.typstorage, a.attnotnull, a.atthasdef,
a.attisdropped, a.attlen, a.attalign, a.attislocal,
pg_catalog.format_type(t.oid,a.atttypmod) AS atttypname FROM
pg_catalog.pg_attribute a LEFT JOIN pg_catalog.pg_type t ON a.atttypid =
t.oid WHERE a.attrelid = '34093'::pg_catalog.oid AND a.attnum >
0::pg_catalog.int2 ORDER BY a.attrelid, a.attnum

Running: [pg_dump --data-only postgres > postgres.dat]
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR: could not find hash function for
hash operator 33639
pg_dump: The command was: SELECT a.attnum, a.attname, a.atttypmod,
a.attstattarget, a.attstorage, t.typstorage, a.attnotnull, a.atthasdef,
a.attisdropped, a.attlen, a.attalign, a.attislocal,
pg_catalog.format_type(t.oid,a.atttypmod) AS atttypname FROM
pg_catalog.pg_attribute a LEFT JOIN pg_catalog.pg_type t ON a.atttypid =
t.oid WHERE a.attrelid = '34093'::pg_catalog.oid AND a.attnum >
0::pg_catalog.int2 ORDER BY a.attrelid, a.attnum

thoughts? (I'm on Version 8.4.3)

thanks in advance