This is the key bit of information:
According to the Linux Wireless page
, that devices is not supported with b43 and b43legacy drivers, but this might be an alternative: http://linuxwireless.org/en/users/Drivers/brcm80211
Since you are using Ubuntu, before you try that, I would suggest looking in the control center (I forget exactly how it's worded, but I think it's under "Hardware") for the "Additional Drivers" item (again, I'm not exactly sure of the wording, it's been a long time since I used Ubuntu 10.x), with the wired connection working
. With my Dells, Ubuntu successfully found the required Broadcom drivers when I did that.
Please keep us posted.