--- step_ui.cc.old	2004-07-11 06:14:10.000000000 -0400
+++ step_ui.cc	2004-07-15 19:38:28.000000000 -0400
@@ -196,6 +196,12 @@
 StepUI::value_display_button_release (GdkEventButton *ev)
 {
 	switch (ev->button) {
+	case 5:   // mouse wheel down
+		step.set(step.val() - 1);
+		break;
+	case 4:   // mouse wheel up
+		step.set(step.val() + 1);
+		break;
 	case 3:
 		if (step.is_enabled()) {
 			step.disable ();