Should export_image_for_release work at stage 2?

The README states that the image after stage 2 should be bootable but I have found that

```
./helper export_image_for_release out/stage2.qed stage2.img
```

fails at the point

```
/etc/init.d/fake-hwclock stop
```

I believe that the fake-hwclock package is installed at stage 3. Is export_image_for_release expected to work at stage 2 or is there another way to create the image?
