Okay, start COD4 and cancel the update that comes up.
(This is where ACCOUNT MANAGER SIGN IN IS.) You must login or register to view this content.
Press your PS button, and go to account manager part. (Your see it saying 'sign-in'.)
Sign in approx, 2 times, when you have done that, skip the CINEMATIC.
Now go into multiplayer (DON'T CLICK PLAY ONLINE.)
Now press the PS button again, and sign in.
Carry on cancelling the update and signing in like you would normally, your know when you have bypassed, as you sill see the big smiley face with the text beside it saying 'Account Manager'
A few things that can make bypassing easier:
Having 60+ friends click You must login or register to view this content. to add and post PSN'S.
Does this work? click You must login or register to view this content.to see peoples feedback on the 60+ friend's theory. +REP if it helps you.