diff -r 58ebbfd10563 src/order_gui.cpp
--- a/src/order_gui.cpp	Fri Mar 19 13:54:42 2010 +0100
+++ b/src/order_gui.cpp	Fri Mar 19 13:54:47 2010 +0100
@@ -465,6 +465,7 @@
 	};
 
 	int selected_order;
+	OrderID order_over;     ///< The order we're currently dragging another one over.
 	OrderPlaceObjectState goto_type;
 	const Vehicle *vehicle; ///< Vehicle owning the orders being displayed and manipulated.
 
@@ -693,6 +694,7 @@
 		this->InitNested(desc, v->index);
 
 		this->selected_order = -1;
+		this->order_over = INVALID_ORDER;
 		this->owner = v->owner;
 
 		if (_settings_client.gui.quick_goto && v->owner == _local_company) {
@@ -953,6 +955,16 @@
 			/* Don't draw anything if it extends past the end of the window. */
 			if (!this->vscroll.IsVisible(i)) break;
 
+			if (i == this->order_over && i != this->selected_order) { 
+				/* Highlight dragged order destination. */
+				uint left  = rtl ? r.right - index_column_width : r.left + WD_FRAMERECT_LEFT;
+				uint right = rtl ? r.right - WD_FRAMERECT_RIGHT : r.left + index_column_width;
+				uint top = (this->order_over < this->selected_order ? y : y + line_height) - 1;
+
+				SpriteID sprite = rtl ? SPR_ARROW_LEFT : SPR_ARROW_RIGHT;
+				Dimension sprite_size = GetSpriteSize(sprite);
+				DrawSprite(sprite, PAL_NONE, rtl ? right - sprite_size.width : left, top - (sprite_size.height / 2));
+			}
 			DrawOrderString(this->vehicle, order, i, y, i == this->selected_order, false, r.left + WD_FRAMETEXT_LEFT, middle, r.right - WD_FRAMETEXT_RIGHT);
 			y += line_height;
 
@@ -1188,6 +1200,12 @@
 		}
 
 		ResetObjectToPlace();
+
+		if (this->order_over != INVALID_ORDER) { 
+			/* End of drag-and-drop, hide dragged order destination highlight. */
+			this->order_over = INVALID_ORDER;
+			this->SetWidgetDirty(ORDER_WIDGET_ORDER_LIST);
+		}
 	}
 
 	virtual EventState OnKeyPress(uint16 key, uint16 keycode)
@@ -1249,6 +1267,12 @@
 		}
 		this->RaiseWidget(ORDER_WIDGET_GOTO);
 		this->SetWidgetDirty(ORDER_WIDGET_GOTO);
+
+		if (this->order_over != INVALID_ORDER) {
+			/* End of drag-and-drop, hide dragged order destination highlight. */
+			this->order_over = INVALID_ORDER;
+			this->SetWidgetDirty(ORDER_WIDGET_ORDER_LIST);
+		}
 	}
 
 	virtual void OnMouseLoop()
@@ -1268,6 +1292,28 @@
 		}
 	}
 
+	virtual void OnMouseDrag(Point pt, int widget)
+	{
+		if (this->selected_order != -1 && widget == ORDER_WIDGET_ORDER_LIST) {
+			/* We are dragging an order... */
+			OrderID from_order = this->OrderGetSel();
+			OrderID to_order = this->GetOrderFromPt(pt.y);
+			uint num_orders = this->vehicle->GetNumOrders();
+
+			if (from_order != INVALID_ORDER && from_order <= num_orders) {
+				if (to_order != INVALID_ORDER && to_order <= num_orders) {
+					/* ... over an order. */
+					this->order_over = to_order;
+					this->SetWidgetDirty(widget);
+				} else if (from_order != to_order && this->order_over != INVALID_ORDER) {
+					/* ...  outside of the orders list. */
+					this->order_over = INVALID_ORDER;
+					this->SetWidgetDirty(widget);
+				}
+			}
+		}
+	}
+
 	virtual void OnResize()
 	{
 		/* Update the scroll bar */