Problem with simple select, RestrictionClauseSelectivity ERROR

Hello,

I have a very simple select , and get an error back I do not understand
:
rhalloc=> select id from groupe where species='mouse';
ERROR: RestrictionClauseSelectivity: bad value
-170141183460469231731687303715884105728.000000

I can select on all the other fields. The field species was added after the
creation of the table, and the data in that field added at that time.
What have I done wrong? thanks for any pointers, here is all my table def (and
data since there are only 3 rows !)

The table is very small :
rhalloc=> select * from groupe;
id|contact_id| sub_date|size|release_date|status |species
--+----------+----------+----+------------+-------+-------
1| 31|23-04-1998| 474| |pending|mouse
2| 36|03-08-1998|3496| |pending|mouse
3| 3|28-05-1998| 799| |pending|mouse
(3 rows)

and here is the format :
rhalloc=> \d groupe

Table = groupe
+----------------------------------+----------------------------------+-------+
| Field | Type | Length|
+----------------------------------+----------------------------------+-------+
| id | int4 not null | 4 |
| contact_id | int4 not null | 4 |
| sub_date | date not null | 4 |
| size | int4 not null | 4 |
| release_date | date | 4 |
| status | text not null | var |
| species | text | var |
+----------------------------------+----------------------------------+-------+

cheers

pat

=======================================================================
Dr. Patricia Rodriguez-Tome | URL: http://www.ebi.ac.uk
R & D Coordinator
The EMBL Outstation, Hinxton - The European Bioinformatics Institute
Wellcome Trust genome Campus, Hinxton | Tel: +44 (0)1223 494 409
Cambridge CB10 1SD, UK | Fax: +44 (0)1223 494 468
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