why 17 Oct' 2008 the Sun will rise continuously for 36 hours

Coming October 17 the sun will rise continuously for 36 hours (1.5 days) in this time the US countries will be dark for 1.5 days.It will convert 3 days to big days.It will happen once in 2400 years.is it possible??I searched in NASA website but Icould't get any information.Experts says that it's only a rumour .