Does anybody know of a good code-example of a foreign key relation
implemented in Hibernate / Struts2?

The main problem I'm facing is how to display the relation in both
table-view (with the foreign key in a column) and form-view,
with the foreign key as a select-box using <s:select>.

In the table-view I get the following result:
Company--------------Owner
Some company-------ognl.NoConversionPossible

In the form-view, I get the following error, when submitting:
Invalid field value for field "company.owner".

Any help would be appreciated