Oracle's months_between -function

Hi, is there an obviuos explanation to this case; months_between -function seems to act a little weird with time given: =========== select months_between(to_date('02.02. 2010','dd.mm.yyyy'),to_date ('01.02.2010', 'dd.mm.yyyy')) from dual ---> 0.0322 =========== ... and then we add times to the mask ===========