There is a problem with the realtime-Clock emulation
23:55...23:59...24:00...24:01...24:10...

At the end of the day the time exeeds 24:00 e.g. 24:15 using the old day's date

to reproduce this problem just set your Windows time to 24:00
your dosbox to 4Dos
and type DATE
you'll see that the time overflows to 24:15 and so on

Bernhard Hartl