select count(*) from table;
Results: 168466 rows
select count(*) from table where column=0;
Results: 168466 rows
select count(*) from table where column<>0;
Results: 168466 rows

When I do a "select column from table where client_id=0 limit 5;" I see correct non-zero values in the result although the selection condition is that the column value must be 0.
I put the data on another instance/machine - I don't see this issue.

Plz find a screenshot@ https://picasaweb.google.com/115470548136322675830/January212013?authuser=0&authkey=Gv1sRgCIDllbOOmqDqOQ&feat=directlink

Another case:
sql>select count(*) from table2 where column2=0;
| 391326 |
sql>select count(*) from table2 where column2<>0;
| 141108 |
sql>select count(*) from table2;
| 399326 |
sql>select column2 from table2 where column2=0 limit 5;
+-----------+
| column2 |
+===========+
|        53 |
|        53 |
|        53 |
|        53 |
|        53 |
+-----------+
5 tuples (156.631ms)

Regards, 
Tapomay