If you are stuck using MCI, buy a prepaid card (the largest denomination you can find). MCI's customer service can tell you how many "units" a call from Kenya will be. It wouldn't surprise me that it's in the range of ten "units" per minute.
However, if you can find a card for 14 cents per minute/unit (Target had MCI cards at this price last week), this would peg the Kenya call at $1.40/minute. Charging the call to a "credit" phone card might be another dollar per minute, or more.
[This message has been edited by Craig6z (edited 02-18-2000).]