Add an easing function to a PointAnimationUsingPath

Question

How could I add an easing function to my PointAnimationUsingPath?

It hasn't a EasingFunction property like the DoubleAnimation has.

Here's my animation:

<PointAnimationUsingPath
        Storyboard.TargetName="MyAnimatedEllipseGeometry"
        Storyboard.TargetProperty="Center"
        Duration="0:0:.8" 
        RepeatBehavior="Forever">

    <PointAnimationUsingPath.PathGeometry>

        <PathGeometry>
            <PathFigure>
                <BezierSegment Point1="0 0" Point2="200 -300" Point3="400 0"/>
            </PathFigure>
        </PathGeometry>

    </PointAnimationUsingPath.PathGeometry>

</PointAnimationUsingPath>

I'd like to add this easing function:

<CubicEase EasingMode="EaseInOut"/>

Is there a way to do it, or should I use an other method? I precise that I want to use a Bezier curve as path for the animation.