[boost] [graph] property_value no longer valid for bgl_named_parameters

The transition from Boost 1.49 to 1.51 gave me a breaking change in the graph library: Originally I used the property_value struct to get the type of a named parameter, like this: property_value<bgl_params, Tag>::type; This no longer works and the current use seems to be: get_param_type<Tag, bgl_params>::type; Is this a regression? Or was I just using the library in the wrong way? Thanks, Alex