Are you the guy who asked about the plantains a couple weeks ago? No luck finding any info on it? Darn, I was hoping you came up with something!
A couple of weeks back a guy had posted a thread about South African beers....he came back from there and was interested in re-creating some. He might have some info...though since his interest was SOuth Africa, his stuff is probably more influence by germanic lager and pilsners than with using traditional ingredients....
One thought...thread search for "gluten free" and organic recipes, here or on the web...I know a lot of people who are wheat intolerant have come up with sourgham based recipes....they may give you some basic recipes from which combining with any research you find about traditional african brewing, you may be able to "fudge" the numbers in a brewing program and be able to brew something close....
Also take a look at John Mosher's radical brewing book and website
http://www.radicalbrewing.com/ he's got some "multi ethnic" beer recipes than use some indegenous ingredients from around the world...you may find the names of some traditional african brewing ingredients there...I know he sells a lot of ingredients not commonly found in traditional brewing enviroments.
Again, you may not find plainly articulated and transcribed traditional recipes, especially if they were brewed by cultures that handed info down orally (I can't see any Akie tribesmen posting on a website their recipes.) You may have to combine many different source material, some of which is pretty loose. or obtuse with modern brewing ingredients, and from contemporay styles that may have evolved from indegineous cultures, to come up with what you "think" might have been brewed by them.
Remember that they would have brewed with whatever they grew around them...If they didn't grow wheat oats or other grains, they probably didn't make what we think of as beer. They may have converted starches (into sugars) from roots instead.
ANd they probably relied on open fermentation instead of yeast cultures.....
I'd really be interested in what you come up with...Please keep me posted.