I take it this is a secure wireless network?
I had a bit of trouble setting an eeepc up when I first did it.
For me the wireless manager wouldn't work at all. I had to go into the network manager and setup the wireless through that. Don't know why it should make any difference since it just gives you the same dialogs... Though setting it up that way does give a nice tick box that lets you save the network for next time.
I also found it was extremely easy to mistype the passphrase on the teeny tiny keyboard.
one other thing... I hear the eeepc sometimes gets confused when a wpa key has numbers in it, thinks an ascii key is really hex and bombs out.
Your mother ate my dog!