Types for Action Pins

[Van Lepthien]

When I create an Activity parameter, I can assign a Primitive Type to it (Integer,Boolean,String,UnlimitedNatural).

If an action pin attached to a CallBehaviorAction is associated with a parameter of the called activity, I can see the pin's properties (inherited from the parameter) by right clicking on the pin (an Arguments popup appears).

If I create an activity diagram and attach pins to an atomic Action, I see how I can associate an Instance Classifier with the pin, but I don't see how I can associate a primative type. A pin is supposed to be a TypedElement, just as a Parameter is. Apparently all TypedElements are not created equal.

Or am I just missing something?