[Laszlo-user] "on" event not sent when attribute updated with same value?

[m . laszlo-user]

Is it considered correct behavior, when an attribute is 'updated' with same value, that the "on changed" event is not generated?  Specifically, in my case I am 'updating' a view's resource with URL of same value, but which has an updated image data, and thus I need the updated image to load.  But OL does not generate the "onresource" event in this case. I wonder, should the "on changed" event mechanism fire anytime the attribute is touched, regardless of the old/new value?