JPA Named Query for sql 'is not true'

Question

I am using JPA with hibernate and named query and I need have a named query like this:

findInstancesByCol1NotEquals(Boolean.TRUE)

This generates sql like this:

select * from instance where col1 <> true;

But I have entries with null values that did not came in the query results.

So what I really need is a named query that generates sql like the following:

select * from instance where col1 is not true;

I already try 'findInstancessByCol1IsNot' but it does not work.

Anyone knows how I can get what I need?