QPrinter::setOutputFormat changes paper size when in landscape orientation

#include <QtGui>
int main(int argc, char ** argv) {
  QApplication app(argc, argv);
  QPrinter printer;
  printer.setOrientation(QPrinter::Landscape);
  printer.setPaperSize(QSizeF(8.5, 11), QPrinter::Inch);
  qDebug() << printer.orientation() << printer.paperSize(QPrinter::Inch);  // 1 QSizeF(11, 8.5) 
  printer.setOutputFormat(QPrinter::PdfFormat);
  qDebug() << printer.orientation() << printer.paperSize(QPrinter::Inch);  // 1 QSizeF(11, 8.5) 
  printer.setOutputFormat(QPrinter::NativeFormat);
  qDebug() << printer.orientation() << printer.paperSize(QPrinter::Inch);  // 1 QSizeF(8.5, 11) 
}