Hi Andreas,

it depends from the interrupt type.

E.g. low level activated interrupts can easy be served to feed it all into a NAND gate (74HC30) and its output to the interrupt input (IT0 or IT1).
Set your micro to high level activated interrupt (as described on my "User Page").
To distinguisch, which interrupt was activated, read all 8 lines with a 3- state driver (74HC541).


Peter