Track change in VISIO 2007 - delete shapes

[T]

Hello,

I am aware that I can used 'track change' in VISIO 2007 but it only seems to
allow me to add shapes,etc but not to delete anything. I know the original is
a protected but I thought it would work like tracking in Word where you can
delete, insert, etc and that is 'tracked'

Is there a function I'm meant to turn on to allow me to delete a shape in?
Or do i cross it out with 'ink'?

Any assistance will be appreciated.

T