Gallery of UML sequence diagrams
This UML sequence diagram is one of the examples included in the Trace Modeler distribution.
It demonstrates the right-to-left diagram layout and bidi support for Arabic script. Note how the various elements adapt to the right-to-left layout direction.
(I've also written an article about the left-to-right bias in UML sequence diagrams)
The bitmap was created by exporting the file 'example arabic.trace' in the examples folder of your installation, at 72dpi and 100% scale in png format.