Nominatim setup error

Hello, I am getting this errors bellow when I run ./setup --index, or ./setup --all --osm-file ./panet.osm What is causing the problem? I have postgresql 9.1 and postgis 1.5.4 installed. Thank You

index_placex: UPDATE failed: ERROR:  operator does not exist: bigint[] @> integer[]
LINE 1: select * from planet_osm_rels where parts @> ARRAY[NEW.osm_i...
                                                  ^
HINT:  No operator matches the given name and argument type(s). You might need to add explicit type casts.
QUERY:  select * from planet_osm_rels where parts @> ARRAY[NEW.osm_id::integer] and members @> ARRAY['n'||NEW.osm_id]
CONTEXT:  PL/pgSQL function "placex_update" line 133 at FOR over SELECT rows
index_placex: UPDATE failed: ERROR:  operator does not exist: bigint[] @> integer[]
LINE 1: select * from planet_osm_rels where parts @> ARRAY[NEW.osm_i...
                                                  ^
HINT:  No operator matches the given name and argument type(s). You might need to add explicit type casts.
QUERY:  select * from planet_osm_rels where parts @> ARRAY[NEW.osm_id::integer] and members @> ARRAY['n'||NEW.osm_id]
CONTEXT:  PL/pgSQL function "placex_update" line 133 at FOR over SELECT rows
index_placex: UPDATE failed: ERROR:  operator does not exist: bigint[] @> integer[]
LINE 1: select * from planet_osm_rels where parts @> ARRAY[NEW.osm_i...