Somalia hasn't had a national government in 25 years, so there's no central authority to regulate the money supply or print currency.
Consequently, 98% of the bank notes in circulation are now poor-quality counterfeits, and buyers and sellers know they're fake.
The market has reached an equilibrium, with a single 1000-shilling denomination that trades at approximately the cost to print it.
Hyperinflation ends when the value of the currency equals the cost to print it, and when the population won't accept arbitrarily larger denominations.
You don't need a government to create a useful currency. Hyperinflation can begin and end with or without a government.
I suppose that what you mean is that hyperinflation will stop at some point, not that it "can't happen". If you destroy the 80% of the economy what follows is hyperinflation. Never mind if you are in the gold standard, a fiat system or whatever.
>"The real question is, what happens to governments that causes them to respond to supply problems with inflationary policy?"
What happens is, it seems to me, obvious. You have to keep the services running, so, you have to pay people, but the money is not valuable anymore, so, you have to give more.
What it seems that you are insinuating is that a country would be better off if the government would not try to keep the country running. I don't think this is the case. But I suppose that it is the real question.
Edit: Nonexistent government is also a government problem - I didn't mean it in that way, I meant it in the sense of "problem related to government!"
As for "how can you keep things running when the supply-side collapses," you could replace inflation with taxes. You could achieve the same re-assignment of value explicitly instead of implicitly: people would end up just as robbed, but the currency wouldn't have to end up devalued. (This might end up helping the economy and making people less poor in the end, since it would mean that you still get to think about your inflationary/deflationary policy decisions. Essentially nobody would choose the regressiveness/progressiveness profile of hyperinflation if given the option, and would instead probably prefer to arrange the necessary pain in some other way.)