I've tried following the guide and my card is still does not appear under list_cores. I also tried executing the following:

root@bt:/lib/modules/fglrx# ./make_install.sh
root@bt:/lib/modules/fglrx# modprobe fglrx
root@bt:/lib/modules/fglrx# pyrit list_cores
Pyrit 0.2.3 (C) 2008, 2009 Lukas Lueg - Project Hosting on Google Code[/url]
This code is distributed under the GNU General Public License v3

The ESSID-blobspace seems to be empty; you should create an ESSID...

The following cores seem available...
#1: 'CPU-Core (x86)'
Inconsistency detected by ld.so: dl-close.c: 719: _dl_close: Assertion 'map->1_init_called' failed!

My system is a clean install of BT4-pre-final. I'm running an Intel Xeon 3110 and an ATI Radeon 4850. I'm about to give up and buy an nVidia card. Can anyone help with this?

Got it working. I didn't realize that stream requires running in graphical mode. I executed startx and now my graphics card appears.