Professor Daniel Robinson of Oxford, in a very nice lecture series entitled Consciousness and Its Implications (Alex take note!), spends some time discussing rule following from a Wittgensteinian perspective. As Wittgenstein carefully demonstrated, "following a rule" is not at all the simple thing it appears to be at first glance.
Professor Robinson illustrates this point with the example of a "No Smoking" sign in a restaurant. He considers three different reactions to the sign by people who we can imagine to be alien to American customs to varying degrees. (Robinson actually makes the third reactor a space alien.)
1) Person one understands "smoking" to mean the direct inhalation of tobacco products. However, as he enjoys the smell of tobacco burning, he simply lights a cigarette and leaves it burning on a plate at his table, thinking he is not thereby smoking. He has violated the rule, despite thinking that he is following it.
2) Person two understands that it is okay to smoke outside the restaurant. But the way he does this is that he pops his head out the door and inhales a drag off of a cigarette, then comes back inside to continue his conversation while exhaling. He also has violated the rule despite his attempt to follow it.
3) Robinson's space alien, who happens to have picked up the cigarette habit, comes from a place that has some symbols in common with the Latin alphabet. In particular, the symbols 'S' and 'K' signify a sacred space, in which it would be a grave offense to the gods to burn anything. So he refrains from smoking so as not to give offense to the gods. Even though his behavior conforms to what the restaurant wants, he is not following the actual rule in place.
The point of all this is that, as Wittgenstein noted, understanding and following a rule often entails a fair amount of knowledge of the cultural context in which a rule is embedded.