SELECT WHERE NOT, is not working

I have a small table in which I have a Character(1) field called reengine.
The field either has an "X" or is empty. This field does not have NULL
values. There are 27 records in the table, 25 are marked with an 'X' in
reengine.

I am querying the table from pgadmin v1.1.0 for windows.

When I write
select count(*) from resource where reengine = 'X';
the result is 25

when I write
select count(*) from resource where NOT (reengine = 'X');
the result is zero even though there are two records without the 'X'.

I have also tried:
select * FROM RESOURCE where reengine > 'X';
select * FROM RESOURCE where reengine < 'X';
select * FROM RESOURCE where reengine = '';

but nothing works except the " reengine = 'X' "

I have other fields in this table that I can query with the "NOT" and the
query works.

The records are being written with insert statements from a Windows2000
computer using ODBC.

Can someone explain this. I tried looking in archives but didn't find
anything.

*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
***
Margaret Gillon, IS Dept., Chromalloy Los Angeles, ext. 297