Updating the issue myself: following the forum discussion:

2.1.4 Primary Keys and Entity Identity

The primary key (or field or property of a composite primary key) should be one of the following types: any Java primitive type; any primitive wrapper type; java.lang.String; java.util.Date; java.sql.Date. In general, however, approximate numeric types (e.g., floating point types) should never be used in primary keys. Entities whose primary keys use types other than these will not be portable.

Si I added a numeric Id to the table. But the result was the same.
To be continued...