The Jargon File (version 4.4.7, 29 Dec 2003):

Dr. Fred Mbogo
 /@m?boh'goh, dok?tr fred/, n.

    [Stanford] The archetypal man you don't want to see about a problem, esp.
    an incompetent professional; a shyster. ?Do you know a good eye doctor?? ?
    Sure, try Mbogo Eye Care and Professional Dry Cleaning.? The name comes
    from synergy between bogus and the original Dr. Mbogo, a witch doctor who
    was Gomez Addams' physician on the old Addams Family TV show. Interestingly
    enough, it turns out that under the rules for Swahili noun classes, ?m-? is
    the characteristic prefix of ?nouns referring to human beings?. As such, ?
    mbogo? is quite plausible as a Swahili coinage for a person having the
    nature of a bogon. Actually, ?mbogo? is indeed a Ki-Swahili word
    referring to the African Cape Buffalo, syncerus caffer. It is one of the ?
    big five? dangerous African game animals, and many people with bush
    experience believe it to be the most dangerous of them. Compare Bloggs
    Family and J. Random Hacker; see also Fred Foobar and fred.