UML 2 Sequence diagram and gates and diagram refs

[russelldb]

Hi,
How on earth do you connect a message from an object to an instance of a sequnce reference. I can drag a sequence diagram onto the current sequence diagram as an "interaction occurence" but I cannot connect any messages from timelines to it!!

Also a config box appears asking for arguments, return values and attribute name. What goes in here ? Argument types or values ? return TYPES or VALUE and what is the attribute name ?

Also if a diagram is a sub sequence type diagram how can I create a gate so that messages come from outside the diagram to the first object ? Seems that all messages must originate on the diagram so how are sub sequnce diagrams supported in EA ?

regards

Russell