             // implementation.
             oldPageSize = pageSize;
             pageSize = Math.abs(viewport.getHorizontalScrollPositionDelta(
-                (increase) ? ScrollUnit.PAGE_RIGHT : ScrollUnit.PAGE_LEFT));
+                (increase) ? NavigationUnit.PAGE_RIGHT : NavigationUnit.PAGE_LEFT));
         }
         super.page(increase);
         if (viewport)

            // implementation.
            oldStepSize = stepSize;
            stepSize = Math.abs(viewport.getHorizontalScrollPositionDelta(
                (increase) ? ScrollUnit.RIGHT : ScrollUnit.LEFT));
        }
        super.step(increase);
        if (viewport)

package spark.components
{
import spark.components.supportClasses.ScrollBar;
import spark.core.NavigationUnit;
import spark.core.IViewport;
import mx.core.ILayoutElement;
import mx.events.PropertyChangeEvent;
