This can typically occur when you are trying to access a field of primitive type (int, double) when there are null values in the database. As this can't be represented at the CMP level, you run into problems.
A possible solution is to define your fields as Integer or Double.
whenever you are deploying an entity bean that has referntial integrity at database level (primary key-foreignkey relationship) see that you have defined both Home, Localhome & Remote, Local Component interfaces in both the entity bean.
and make sure that they are mentioned in the ejb-jar.xml
can you explain why i should put the home and interface in the <ejb-class> section?
do you know how i can do it with xdoclet?