Para - the document that is signed when you arrive in wonderful Australia is so general "Have you got anything of interest to customs" that they can get you on anything they want.
Rumour has it that the "child" porn he had was the infamous "Tammy video". This is a home made on the phone video recorded by a female school student, and a national service boy, in Singapore, having sex. Every second man in Singapore has seen it, or has it, in some form of media. The other porn was Japanese stuff above age. Again rumour
If this is the case then I feel he has been really hard done by and I hope that the company stick by him. If he has the commercially produced pedophile porn then throw the book at him.