Zimbabwe allows foreign currancy

From the uKTelegraph

..."Some of you may ask, 'are we now trying to dollarise the economy?' No, the Zimbabwe dollar remains the legal tender," Mr Gono insisted.

But de facto dollarisation has been under way for weeks and months. Carrying ever-larger bundles of increasingly worthless Zimbabwe dollar notes is inconvenient for shoppers, let alone businesses, and the US dollar and South African rand, along with fuel coupons, are far more useful alternatives which will not lose half their value in a matter of days.

The move is also partly an attempt to bring more foreign currency into the government's own depleted coffers - by legalising the trade, it hopes to move business from the black market to official channels, where it will collect 25 per cent of private companies' export earnings and 15 per cent of domestic traders'. ...
--------------------

One, this will cut into the black market that buys dollars, Euros, Rands etc.
Two: if the companies don't give a decent exchange rate, things will stay the same.
Three: they need a way for people to send money from outside the country so that the dollars will be given to the person, not Zim currancy at the "official" exchange rate.