FM / BAPI for cheching time collusion?

Hello experts,

i´m looking for a function, that checks two date&time pairs for a collusion.

As example:

Pair 1 - Begin Date is 29.09.2010 time 10:00 End Date is 30.09.2010 time 22:00

Pair 2 - Begin Date is 30.09.2010 time 21:30 End Date is 01.10.2010 time 23:00

So the two pairs collide on 30.09.2010 at 21:30 for half an our.

Does anybody know a function which can handle this?

Thanks

Points guaranted