QEasingCurve is not serialized/deserialized correctly

#include <QByteArray>
#include <QDataStream>
#include <QDebug>
#include <QEasingCurve>
#include <QPointF>

int main()
{
QEasingCurve orig;
orig.addCubicBezierSegment(QPointF(0.43, 0.0025), QPointF(0.38, 0.51), QPointF(0.57, 0.99));

QEasingCurve copy;

QByteArray data;
QDataStream dsw(&data,QIODevice::WriteOnly);
QDataStream dsr(&data,QIODevice::ReadOnly);

dsw << orig;
dsr >> copy;

qDebug() << orig.toCubicSpline().size() << " != " << copy.toCubicSpline().size();

return 0;
}