I think you will find under the customs act that an officer has the right to search any or all or your posessions that you are bringing into the country. Whether it's in your laptop, brief case, wallet, jocks and socks pocket of your suitcase I'd say is irrelevant. I wonder if they will also start clamping down on the pirate DVDs that many people (myself included) usually bring back?
On another note, do customs officers do the internal examination or are suspected individuals sent off to a medical facilty for the latex glove treatment?