In Enterprise Architect I have represented one of our systems as a lane on a BPMN diagram. I would like to reuse that system in various UML sequence diagrams, however when I add the system to a SD it shows as a lane rather than a Lifeline. Any idea how to approach that?
Assuming that you talk about BPMN, the specs say on p. 111
A Pool acts as the container for the Sequence Flows
Lanes are just sub-partitions of pools.
So, it is not an object that has behavior but only surrounds a couple of behaviors.
You would need to create single SDs showing the behavior of actitivities inside a lane. Question is: why use SDs which are meant for technical description if you already described the communication on a business process level?