ANALYZE errors (postgres 8.1.4)

I'm having some problems with ANALYZE.

When I run ANALYZE on a postgis enabled database created by ogr2ogr from
the Census Bureau's tiger data I get the following error for a number of
the tables created:


tiger2005se=# ANALYZE arealandmarks ;
NOTICE:   no notnull values, invalid stats

I can't find any reference to this error.  What does it mean?

Table structure:
tiger2005se=# \d arealandmarks
                                  Table "public.arealandmarks"
    Column    |     Type      |                            Modifiers
--------------+---------------+-----------------------------------------------------------------
 ogc_fid      | integer       | not null default
nextval('arealandmarks_ogc_fid_seq'::regclass)
 wkb_geometry | geometry      |
 module       | character(8)  |
 file         | character(5)  |
 state        | numeric(2,0)  |
 county       | numeric(3,0)  |
 cenid        | character(5)  |
 polyid       | numeric(10,0) |
 land         | numeric(10,0) |
Indexes:
    "indx_mod_arealandmarks" btree (module)
Check constraints:
    "enforce_dims_wkb_geometry" CHECK (ndims(wkb_geometry) = 2)
    "enforce_srid_wkb_geometry" CHECK (srid(wkb_geometry) = 32767)


Thanks,
Tim Bowden
Mapforge Geospatial