From dpkg the #debian channel bot:
[b43] the new driver for modern Broadcom 802.11g wireless chipsets (
http://wireless.kernel.org/en/users/Drivers/b43), included in Linux since 2.6.24. Use <b43-fwcutter> to extract version 4 firmware for this driver. USB devices are not supported (for 4320, see <rndis_wlan>). 802.11b-only devices and BCM4306 rev 2 are rather supported by the <b43legacy> driver.
http://wiki.debian.org/bcm43xx
From the sidux wiki:
Broadcom, b43/ b43legacy wlan:
apt-get install b43-fwcutter