swapping shapes

[vwf <vwf vulkor net>]

Hello,

I have a series of shapes that are identical except for the image. Now I
would like to be able to swap one shape for another one on the canvas.

When I look at the .dia file this should be achievable: change in
<dia:object type="mysensiblename" version="1" id="O1">
"mysensiblename" for "anothersensiblename"

But I would like to do this on the canvas, preferably using the mouse. 
Could this be done? (and is so: How?)

Thanks,
Frits