Some /film/film instances have multiple values for initial_release_date property.
Example is:
Gridlock'd [ http://www.freebase.com/view/guid/9202a8c04000641f800000000086440a ]
Is this a bug? The dates do not seem tied to e.g. a release in a particular country, and generally I have noticed that there is a full ISO date and a year-only date value.