Win32 mousewheel events delayed until pointer motion

Hi folks, I’m a newbie to SDL having trouble with
mousewheel events. Using SDL-1.2.5 compiled with
MingW under win98.

Mousewheel events don’t show up until the mouse
is moved, unless a key is held down.

As an example, run the graywin test program. Move
only the wheel. Notice several wheel movements will
queue up until the pointer is moved. Try again with
space bar down. Reaction to wheel is immediate.

Bug or pilot error?

Thx,
Jack Spaar