Fill series event detection

[DrFear]

Is it possible for VBA to detect the event of the user left (or right)
clicking and/or dragging when the cursor at the bottom right of a selection
has changed to a "+" (ie when just about to fill a series - but before
filling the series) ?

Could I perhaps detect the status of the cursor in a standard
_BeforeRightClick event?

I would like to run a custom macro to usurp the normal action.

Can the subsequent default fill series action be cancelled?

(using Excel 2002 SP3)

Thanks for any suggestions