[Boost-users] [date_time] binary serialization / integer representation

Hello, I would like to serialize date_time types to a binary archive, and/or convert them to, say, a integer types. I see the counted time system does use a 64 bit integer for ptime, but doesn't provide access to it. Is there something available for this use, or should I create a conversion function? Thanks in advance, Cheers, Rutger