C'mon don't misrepresent the high court case.
"Corruption is a form of dishonest or unethical conduct by a person entrusted with a position of authority, often to acquire personal benefit"
In this case, the donator was in a position of authority not the receiver - further there has been not even a hint of personal benefit being asked for, inferred or delivered. Indeed it was unethical because he knew it was illegal, hence the cash nature of the political donation. Because of that it isn't a bribe and he received no benefit, and certainly no more benefit than any other donator to any political party.
When you start to include anything illegal within a political context, you dilute the gravity and meaning of corruption. Eddie Obeid was corrupt, but potentially hasn't broken a law , but we know that is corruption, and classicly so.
It's not irrelevant that it was only in that term of the labor govt that donations by developers to political parties was banned and I think only in NSW. It would have seemed as a law to have some political motivation to strangle the opposition of funds while leaving Union donations untouched, though not an argument easily won in public post hoc.