[OSM-newbies] postgis import

[Adrian]

I'm trying to get a section of osm into postgis, following the 
instructions in the wiki for Mapnik

http://wiki.openstreetmap.org/index.php/Mapnik#Loading_Data

but I can't get past the stage of loading lwpostgis.sql into the 
database - I get the error messages below. This is on a newly created 
Debian 4.0r2 box installed specifically for this task.

I've tried reinstalling postgres and postgis packages and I've 
definitely done the createlang stage.

Any ideas?

psql:/usr/share/postgresql-8.1-postgis/lwpostgis.sql:39: NOTICE:  type
"histogram2d" is not yet defined
DETAIL:  Creating a shell type definition.
psql:/usr/share/postgresql-8.1-postgis/lwpostgis.sql:39: ERROR:  could 
not load library "/usr/lib/postgresql/8.1/lib/liblwgeom.so.1.1":
/usr/lib/postgresql/8.1/lib/liblwgeom.so.1.1: undefined symbol:
vacuum_delay_point
psql:/usr/share/postgresql-8.1-postgis/lwpostgis.sql:44: ERROR:  current
transaction is aborted, commands ignored until end of transaction block
[repeated lots]