Need Shift and Control to adjust size of step in numericupdown control.

Working in C++.NET 2008.

I need my numericUpDown to have fine-tuneing capability.  That is, it should change by 1 normally, by 10 if shift is pressed, by 100 if control is pressed, and by 1000 if control and shift are both pressed.

My end-user claims to have seen this, but I don't see how to do it.  Any help will be appriciated.

Thank you