I'd like to add to Sancho's answer. His answer is very correct, there is no ban on small-breasted porn models, but there is an "in practice" reality to the claim due to how the censors categorise and interpret the classification systems in Australia.
There is no specific rule stating that small breasts are bad, but in practice many complaints are registered and material is refused classification due to models not looking "adult" enough and can thus be categorized as either child sexual abuse or offensive sexual fetishes.
Publications will be classified ‘RC’:
- (a) if they promote or provide instruction in paedophile activity; or if they contain:
- (b) descriptions or depictions of child sexual abuse or any other exploitative or offensive descriptions or depictions involving a person who is, or appears to be, a child under 18;
- (c) detailed instruction in:
- (i) matters of crime or violence,
- (ii) the use of proscribed drugs;
- (d) realistic depictions of bestiality; or if they contain gratuitous, exploitative or offensive descriptions or depictions of:
- (e) violence with a very high degree of impact which are excessively frequent, emphasised or detailed;
- (f) cruelty or real violence which are very detailed or which have a high impact;
- (g) sexual violence;
- (h) sexualised nudity involving minors;
(i) sexual activity involving minors; or of they contain
exploitative descriptions of:
- (j) violence in a sexual context;
- (k) sexual activity accompanied by fetishes or practices which are revolting or abhorrent;
- (l) incest fantasies or other fantasies which are offensive or revolting or abhorrent.
As you see, this list is quite open to interpretation. Thus the review board for published materials and the complaints board for online material often do classify materials as RC, regardless of their legality.
It is illegal to sell RC material in, say, a newsagent. It’s also
illegal to make it available for viewing publicly.
But it’s not by any means illegal for me to own or possess these
things myself and view them in the comfort of my own lounge room. It’s
quite legal, for example, for me to own and view (or read, or listen
to):
An RC film, TV program or other video such as Ken Park or Baise Moi;
Material on euthanasia such as The Peaceful Pill Handbook;
Material that instructs on bomb-making, theft or any other crime.
Now, sure, some of these things are distasteful to many people. Even
offensive. Or morally problematic. And they are all refused
classification.
But they are not illegal.
So the RC classification often has material on its list despite that material being perfectly legal. This list includes movies, books, video games and internet sites.
But how do small breasted models fall under this classification system? Well, in practice, many RC classifications have been passed against many magazines, such as the Hustler Barely Legal series, Just 18 magazine, New Climax, and of course, various DVDs like this and this. The TV show Hungry Beast did several segments on censorship of porn in Australia, including covering the issue of small breasts and exposed labia lips, which was leading to photoshopping of models.
The best example of the bias against small breasts is from the leaked Australian Internet Filter Blacklist compiled by ACMA. This list of sites was not only a disgrace, as legitimate sites were being blacklisted and didn't realise, but many of the supposed "illegal" or RC sites were perfectly legal. The problem was that they featured small breasted women. For example, Abby Winters, Just Teen, Teens Naked and Tube8, all legal, all acceptable, all models over 18, are on the blacklist. The common theme to many of the banned porn sites is that there are small breasted women or women who "appear to be" too young. The distinction of "too young" is obviously ambiguous and thus many models are RC'd because small breasts is a sign of "young" women.
It is also worth reading the list to see the sort of sites that were being RC'd, because you will see many perfectly legal sites on the list. I suspect, as is outlined in the Wikileaks article, that complaints are lodged for any hardcore sex sites that a complainant comes across "by accident" and it is duly listed regardless of whether content ticks the points I outlined above.