Could the existence of Hell as a place of eternal punishment be morally justified?

Hell has been used throughout the centuries by religion as the place where all those who do not enter heaven will be sent, to face punishment for all their sins. However, there is a problem associated with the existence of hell, especially if the idea that there is a morally perfect theistic god is proposed. The idea that there is an irreversible hell where people can be sent would be incompatible with the theistic god, for primarily the fact that no matter what the sin has been, the core component of justice is that the punishment should be equal to the sin committed. Therefore, if someone has been sent to be punished for the rest of eternity, then there can be no crime committed that warrants such a punishment. Even with the worst people in the world, their crimes have a time scale on them, they can only do so much bad in their one life time. To be eternally punished for something they did does not appear to be morally justifiable. On the other hand, if it were possible for persons to switch between the two states of heaven and hell, (the so called "second chance" view) then this could perhaps be morally justifiable. However, eternal punishment can be morally justifiable for no crime. Another suggestion is the Annihilationism view, that those who do not get into heaven simply cease to exist. This is also morally unjustifiable however. This would deprive the damned of an eternity of bliss, which is also giving an infinite punishment for what would only have been a finite crime.