Export longer than film

ok thank you for your replies. The Movie has BITC. And within Nuendo everything syncs up. So even if I re import the stereo export, it syncs up. What I do not quite understand is, in Nuendo the film and the stereo export is exactly 01:28:44:10 long. But if I am opening the stereo export with a different program, like say snapper or quicktime outside of Nuendo it says the length is 01:28:49.741. Where do these extra 5+s come from? And why do they disappear again when I import it into Nuendo? Seconds should be seconds, whether I divide them into frames or ms.

Thanks!

Max