Age Limit for Permanent Residency application in Australia..?

My friend who is now 47 y.o. is considering applying for a PR in a couple of months. However, it is mentioned in the immigration requirement that the age limit is 45 years old. I informed him that, but he told me that there is an exemption to this rule...I just would like to know what is that exemption as he would be on a false hope if he thinks that he will still be qualified for a PR.