Actually, we could really change the "use 5.12" to "use 5.10" - I was merely using that line to show everyone what version I was using to develop/test this. Since I also now have the Net::DBUS code working under 5.8.8, then, other than the 'say' lines, this definitely works in earlier-than-5.12 versions of perl.
Be sure when you're using this that you're looking for Passwords and not Maps. As mentioned originally, this does not work with "Maps" in kwallet (though I've opened a bug against KWallet for their unfortunate maps-to-wire format). That is a definite deficiency, and an Excersise For The Reader(TM).
Note that in the original script, the userid/password strings are key names, not credentials. The whole point is to fetch credentials, not know them. So, what keys in your "Network Management" folder in KWallet exist under the "Passwords" group? When you open up the folder in KWallet, this should show up:
[ ] Network Management
+-- Binary Data
| +-- key
You have to use "key", not "walto" or "12345" (which, of course, is the password to my luggage).