How to fill a DropDownList with custom options?

Hi,
I want to populate a DropDownList in netbeans 6.0.1 with values from a custom array. I tried to create an adaequate property in the application bean, but "Add" is greyed out in the context menu. It's the same when I try to do it within the session bean.
So, how can I populate the DropDownList with my own values?
Best regards
Thomas