I reckon it's doctored, was my first impression straight away. reasons:
1. I reckon those people would be absolutely cr@ppin' their daks if that thing jumped that high that close and they all look WAY too calm.
2. I don't think they do croc feeding from that sort of boat, they are more regulated than you would think, even in the NT.
3. I'm pretty sure that boat and that picture look something like I've seen before when he was feeding a White Breasted (or Bellied, same thing) Sea Eagle.
4. The doctoring doesn't look that "real" to me either.
Sorry to burst your bubbles! Have a look at these vids, much more plausible that the Sea Eagle has been replaced by that croc.
http://www.youtube.com/watch?v=1PdaRiYu9UM&feature=related
http://www.youtube.com/watch?v=f6iV4eUdP6A&feature=related (although this one says croc feeding...)