When using the latest wpa_supplicant package from current, yes wpa_supplicant has been moved into current, I get an error about it not being able to find /usr/bin/wpa_cli. It seems that wpa_supplicant now installs itself to /usr/sbin instead of /usr/bin which is causing a problem since there is a reference to wpa_cli on line 117 using its absolute path. I've made a quick patch and posted it as a bug so hopefully this will be fixed in the next initscripts release. In the mean time you can get the patch from the bugs page here. I looked at the pkgbuild and it seems that the change was in wpa_supplicant's make install routine not anything the arch devs did. The patch will change the netcfg script to call wpa_cli with out specifying the path and let the shell figure out where it is. The patch applies to /usr/bin/netcfg.