Simplest and fastest solution is Mad_Gouki's. You need a network connection (presumably wired), start Synaptic package manager, press reload, then find b43-fwcutter, install it, and when asked, search for new firmware.
Worked for me with 4306 Version 2 broadcom wireless card.
Edit: Actually, this only works intermittently.
Edit 2: This on a Dell D400