What you will need a supplicant. You can get xsupplicant, the open source option at
http://www.open1x.org/ . Of course make sure that your card is on the supported hardware list before even downloading it and install the prerequisite OpenSSL -
http://www.openssl.org/ . After you set the essid, did you run iwconfig again to look if it associated itself to an AP? On my school's Leap network I have to furnish a fake encription key to get associated. You could do that by running iwconfig eth0 key 999999999999; replacing eth0 by your actual wireless device. An example of a xsupplicant.conf file that should theoretically work would be:
#example of /etc/xsupplicant/xsupplicant.conf
#for LEAP protocol
network_list = all
#the list of networks to access
default_netname = default
#the default access network
logfile = /var/log/xsupplicant.log
#log file
myssid #here is your network id, may be listed in the network list
{
type = wireless
allow_types = all
identity = <BEGIN_ID>account<END_ID>
eap-leap {
username = <BEGIN_UNAME>account<END_UNAME>
password = <BEGIN_PASS>passwd<END_PASS>
}#setup for leap
}
Modify that file to fit your need and after you network interface has been associted you should run:
ifconfig eth0 up
xsupplicant -c /etc/xsupplicant.conf -i eth0 -f -d 4
replacing /etc/xsupplicant.conf and eth0 by those applicable to you system and you should be able to ping outside the network if everything went as planned.
Don't quote my config file, I haven't actualy tested it.