Famitsu just revealed a password that lets players jump into Assassin’s Solid without the assassin’s emblemk. Head to the Password section and punch in aottrykmyn. Once the password is registered you can select Altair’s costume from the camouflage menu after you obtain Metal Gear Mk. II. The other code listed is for the Type 17 pistol. Input jmsotsynrn to add it to your arsenal. Like Altair's outfit, you receive the Type 17 pistol after the Metal Gear Mk. II.
Images courtesy of Konami.