Soak corn in water for 30 minutes.
While corn is soaking, stir green onions into margarine or butter.
Pack into a small bowl.
Cover and refrigerate until serving time.
(You might consider making two bowls, one with margarine and one with butter, so your guests can have their choice.) Preheat the grill.
Set corn on grid over ashen coals.
Grill for about 5 to 6 minutes, rotating every 2 minutes.
Corn will char on the outside, but the inside will be cooked.