[boost] property map, boost::identity_property_map

Hi, is there any reason, why boost::identity_property_map implementation in <boost\property_map.hpp> is completely different from how it is documented in http://www.boost.org/libs/property_map/identity_property_map.html ? As mentioned in the implementation, boost::identity_property_map is a property map that applies the identity function to integers. On the other hand, documentation clearly states that one can use identity_property_map with any types. Valentin Samko http://val.samko.info