> What I would expect:
> first mouse button: embedded viewer
> middle mouse button: extenal viewer
> 
> This is how it always worked in KDE 3 (and before) as
> well.
> 
> Doesn't it work like that?

Possibly, but that would not resolve the desire to reverse the defaults to set external as the default. Further, not everybody uses "middle clicks." :)

Darrell