This is not necessarily a bug--there's a mismatch between what type of column hibernate is expecting and what type the column actually is.
Since most databases don't have a native boolean type, hibernate represents a boolean values with 1 and 0.
Did you create this database table yourself? If so, just change it to NUMERIC(1).
If not, post details of how you created it? (Did you use hibernate) Maybe someone can suggest the right way to create it.
I let Hibernate create the Database in both cases.
And I tried to change the boolean to numeric in my own Project, but it doesn't solve the problem.
SeamSpace recreates the Database after every deploy so I can't change this column.
I can't believe that this a real bug, postgres isn't that exotic that I am the first one who has this Problem.