The Coalition trusts Rupert, but not you?

So, according to The Australian, Treasury is perhaps a bit peeved that Rudd is using some figures they did before the election was called to contradict Coalition costings of savings.   But, says Treasury, their work wasn't a true costing of Coalition policy: it was more a hypothetical exercise and different assumptions would give different results.

OK.

But here's the thing:  The Australian is saying it has seen the Parliamentary Budget Office costings on public servant cuts that Abbott and Hockey are refusing to release.  (Maybe next week you'll some of their work?):

The costing, seen by The Australian, assumes that natural attrition would see the size of the federal public service cut by 6,000 positions by June 2014 and another 6,000 by September 2015.

So who leaked this to The Australian - the surest source of a sympathetic account for the Coalition that is possible?

I think I should assume that the Coalition is leaking to Rupert what they won't give directly to the public.

How ridiculous is that?