Yes, you have to draw two lines, since the event and the action are part of the line.
as you can see at http://en.wikipedia.org/wiki/File:UML_state_machine_Fig1.png
your string will receive text of type "event1 / action1"and "event2 / action2".
If you do not generate code in a diagram, you can also use one line and add text, for example "event1 / action1 OR event2 / action2", if it is more readable.
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