I wrote a how to document on getting Broadcom wireless adapters working using ndiswrapper, wireless tools, and wpa_supplicant. While it is written specifically about getting things working under Slackware, as long as you know the Kubuntu file equivalents, you should be able to get things working just right.
The URL is http://www.linuxquestions.org/questi...d.php?t=550053
. It is as clear, concise, and geek-speak free as I could write it. Read the entire thread as there are some other things to know that aren't contained in the document itself. It works well, too. I am typing this message under Slackware with my wireless adapter. While I do have a net cable sitting next to this machine, I haven't plugged it in since I got the wireless running.
Please let me know if the document helps.