You can use a number of UDFs that can determine the information you are looking for. One that I worked on a few years ago will do this...

EnumNetworkConnections()
http://www.kixtart.org/forums/ubbthreads.php?ubb=showflat&Number=139601#Post139601

How to use UDFs -
http://www.kixtart.org/forums/ubbthreads.php?ubb=showflat&Number=81943#Post81943

The rest of the UDFs are here -
http://www.kixtart.org/forums/ubbthreads.php?ubb=postlist&Board=7&page=1


Untested, but should give you an idea...
 Code:
for each $connection in EnumNetworkConnections(1)
  ? "The MAC address for " + split($connection,",")[0] + " is: "  + split($connection,",")[1]
next