This experience when i installing backtrack 5, and i got a problem with wicd. Previously backtrack doesn’t include network manager as network tools.
See this screenshot:
For fixed this problem, following step by step:
1. Open your terminal or konsole
1 # dpkg-reconfigure wicd
3. Type again
1 # update-rc.d wicd defaults
4. And then log out your backtrack desktop, if not fixed try to reboot your machine.