ScrollBar WheelMouse not working for me

[ted]

Good day

A really simple example this.

Lazarus 0.2.24,  Windows XP prof SP2.

A new Lazarus project.   Only one Form.

Only components on the Form are an Exit button and
a TScrollbar component. (kind vertical)

The project compiles fine.
( I get two hints about unused ScrollCode and ScrollPos
which is hardly a surprise. )

The ScrollBar functions mainly as could be expected.
The up-arrow works, the down arrow works,
the 'thumb' can be dragged up and down,
one can click on the white areas above or below
the thumb and they work.
Provided that the ScrollBar is in 'focus', the keyboard
Up and Down arrow keys work fine and also the
PageUp/PageDown and Home/End keys.

My question is:  How do I get the mouse wheel to work ???

What am I doing wrong ?   It works great in the Lazarus IDE
so that rules out hardware problems.

Any help would be appreciated.

ted