Near the end of my first year of university I discovered several vulnerabilities in the halls of residence where I was staying. Being an advocate of full public disclosure I wrote the following article for the student newspaper, Felix. The article was published in issue #1437 on the 19th of June 2009 — the last issue of the summer term. To my knowledge it was published verbatim.
In the article it is stated that Mul-T-Lock Classic cylinders are used on the doors. In reality Mul-T-Lock Interactive cylinders are used. Although functionally very similar the Interactive features an interactive pin. The purpose of this pin is both to make the lock harder to impression and enhance key control. This can be discerned by visual inspection of the lock: Interactive cylinders do not have visible wards while Classic cylinders do.
For those that are interested: further information on Mul-T-Lock cylinders can be found in the article Mul-T-Lock: Design and Security published at Lockpicking Forensics.