Check out this link:
http://wiki.debian.org/wl?highlight=(broadcom)|(wl)
Assuming that you are running Ubuntu, or some other Debian based distro, those steps will work. The STA (or wl) driver from Broadcom can be a little finicky at times. Users of the b43 driver sometimes report ONLY being able to connect encrypted access points, while users of the STA driver sometimes report sudden disconnection (signal drop) among other problems. Also, the STA driver has two known bugs.
The first one makes the system call the device eth1, making it seem like a wired network adapter when it's really a wireless device. The second bug messes up iwconfig and related utilities so that they need to run as root for the device to even show up. This means that programs like Conky can't tell you what access point you're connected to unless run as root (which is dangerous with Conky). The only non-root way to use a Broadcom card that works consistently is to use NetworkManager.
Personally, if you can afford it, you should get another wireless card. (just my honest opinion)