BPEL Editor does not observe "Layout Flow children automatically" preference at startup

Imported BPEL processes, or processes that were edited in the BPEL "Source" view will not automatically lay out Flow activity contents even if the "Auto Layout" preference is set. Toggling the auto layout preference does not change the editor's "dirty" bit (and this is correct behaviour) so simply toggling this flag off and back on does not force an auto layout.