Delete statement does not work with PostgreSQL 8.0.1

Hi,

I have just today installed the new version of PostgreSQL (8.1.0),
and my old code seems to have stopped working.

I am basically trying to delete a row from a table:

DELETE FROM "CON" WHERE "ref"='CON5';

I have checked and CON5 is definitively in the CON table. I tried
using JDBC, pgAdminIII and command line but it doesn't seem to work.
I get a message saying 0 rows have been affected, as if the item was
not in the table. Am I doing something wrong? Has the syntax changed
or is this just a bug?

Thanks for your help,
Ledina