Most likely the dbus activation is failing. NetworkManager-0.7.0-0.2.svn2833.fc8 wpa_supplicant-0.5.7-7.fc8
It is. First selinux stomps on it, then it gets an error if you disable SELinux.
I believe at least the "name mismatch" error is fixed in the current snapshots; don't know about selinux.
NM now pokes wpa_supplicant correctly in svn trunk; selinux is still an issue though.