1. Goto Black Ops Multiplayer menu and wait
2. Then tell your friend to go to zombies and wait at the zombies party menu.
3. Now join his session progress.
4. As it takes you back to the Black Ops Main Menu quickly press a on multiplayer before getting the joining session messege
5. it should take you back to the black ops multiplayer menu
6. Now quickly goto local then into system link.
7. now wait until u get the join session messege and then it should turn to a black screen and reload the system link menu with an error say "Unable to join session" or similar
8. Now goto create match, edit game options then go down to class editor and change it to custom classes and press a
9.Press a again goto edit class load out, primary , goto primary again .
10. then from there pick what ever classified gun you want and buy it (this uses real cod points from your account) 11. now when u goto ur online account u should be able to select and use the classified guns u brought even know its say its locked, also with this glitch u can buy pro perks before u unlock them but must do.