I think that Net::Address::Ethernet is the module you are referring to. Whilst the approach of using a native config utility seems somewhat crude it does the job and requires nothing additional to the operating systems as installed. I use that module in end-user workstation type products all the time (I use the MAC address as part of the machines 'fingerprint').

For diagnostic use where I have Perl code in a test and monitoring system for network equipment, we tend to use the Net::SNMP family. Much more capable, but at the same time, much higher overhead and you need to becertain that SNMP MIB's are present in all the machines you need to talk to, I am not sure if this is the case with all flavours of Windows.

jdtoronto