Bug: Application crash during undo (reproducible)

[Bebe Stanie]

Hi,

I've encountered the following reproducible crash in EA:

- Create new project
- Add 2 classes, A and B
- Add operation Test() to B
- Draw interaction diagram between A and B, with message Test() from A to B
- Delete the message (it in the undo queue now)
- Delete B in diagram (no undo possible)
- Press undo, and EA crashes   (its message in the queue is referring to a non existing class)

Hope you can fix it.

Have a nice weekend,
B.S.