#2 failed to join after aspoof

[Anonymous]

After performed the spoof, works fine for displaying under `ifconfig
en1`, Airport menu bar show the detected network, but got error to
rejoining the networks. It only works when I use the original file back.

Wonder what is the problem, software or technical problems? If it is the
latter, please point me out where to fix it.

Using Mac OS X Tiger 10.4.4.
School's open network.