[boost] [lexical_cast] exception type for overflow

Hi! i would expect that lexical_cast<uint16_t>("65536") and numeric_cast<uint16_t>(lexical_cast<int>("65536")) would throw the same exception boost::numeric::positive_overflow. but lexical_cast throws a bad_lexical_cast. is it possible to change lexical_cast so that it also throws positive_overflow if the error comes from the overflow and not from the lexical parsing? -Jochen