Comment 4 for bug 336230

after more testing, it might be that the problem is not really with NetworkManager.

i installed wicd (which uninstalled NetworkManager),
and there it was much easier to see exactly what is happening.
when i set my access point to "not-hidden" mode (broadcast SSID),
then i was able to connect to the WPA1 network.
when i set it to hidden, i was not able to connect to it anymore.
in fact, wicd claimed the network does not exist.

normally at this point i would be suspicious about the access-point,
that maybe it's just broken,
but i am able to connect to it's hidden WPA1 network
without problems from the suse-linux-enterprise-desktop-10,
which is preinstalled on the laptop.