At the 'Main' menu select the 'Community & Extras' option and highlight the 'VIP' selection. Then press the Triangle button and input one of the following codes (without the quotes) to unlock the corresponding unit.
Unlock Russian Spetsnaz Guard Brigade
Enter the code 'SPZA39'.
Unlock Special Spetsnaz Battalion
Enter the code 'SPZT17'.
Unlock European Enforcer Corps
Enter the code 'EUCA20'.
Unlock U.S. Joint Strike Force
Enter the code 'JSFA35'.
Added by: Sanzano Nov 7th 2008, ID#1029