How to scale a transparent org.eclipse.swt.graphics.Image, loaded from a PNG; Java

I have an org.eclipse.swt.graphics.Image, loaded from a PNG, and want to scale it in high quality (antialiasing, interpolation). But I do not want to lose transparency and get just a white background. (I need this Image to put it on an org.eclipse.swt.widgets.Label .)

Does anybody know how to do that? Thank you!

Based on Mark's answer I found a better solution without the "hacky bit": first copy the alphaData from the origin then use GC to scale the image.

public static Image scaleImage(final Device device, final Image orig, final int scaledWidth, final int scaledHeight) {     
    final Rectangle origBounds = orig.getBounds();     
    if (origBounds.width == scaledWidth && origBounds.height == scaledHeight) {     
        return orig;     
    }     

    final ImageData origData = orig.getImageData();     
    final ImageData destData = new ImageData(scaledWidth, scaledHeight, origData.depth, origData.palette);     
    if (origData.alphaData != null) {     
        destData.alphaData = new byte[destData.width * destData.height];     
        for (int destRow = 0; destRow < destData.height; destRow++) {     
            for (int destCol = 0; destCol < destData.width; destCol++) {     
                final int origRow = destRow * origData.height / destData.height;     
                final int origCol = destCol * origData.width / destData.width;     
                final int o = origRow * origData.width + origCol;     
                final int d = destRow * destData.width + destCol;     
                destData.alphaData[d] = origData.alphaData[o];     
            }     
        }     
    }     

    final Image dest = new Image(device, destData);     

    final GC gc = new GC(dest);     
    gc.setAntialias(SWT.ON);     
    gc.setInterpolation(SWT.HIGH);     
    gc.drawImage(orig, 0, 0, origBounds.width, origBounds.height, 0, 0, scaledWidth, scaledHeight);     
    gc.dispose();

    return dest;
}

This way we don't have to make assumptions about the underlying ImageData.