+1  A: 

Specifying the fully qualified name is correct. Otherwise the runtime will only look in the current assembly.

Jakob Christensen
Jakob, thanks for the reply but as noted in my question: I've tried moving my code back into app_code (where it was working previously)and it still does not pick up the unqualified name . I believe I've eliminated the Assembly as a possible source of the problem. Unless there is some caching?
TygerKrash
That is probably because you changed the namespace as well so it is different from the default namespace of your web site. You may want to try using the designer for the ObjectDataSource (by clicking the small arrow besides the ObjectDataSource in the designer).
Jakob Christensen
I believe the Wizard will show you a list of available types.
Jakob Christensen
Jakob, tried the wizard. sure enough its only showing the fully qualified name. Guess thats what I'll have to use then. Thanks.
TygerKrash