having been to heaps of countries in Africa i can only Xena's sentiments.
The Nigerians are universally treated with suspision and seen as dodgy or shifty (as they say in east africa) and feature in the crime pages of many african dailies.
The first piece of advice i was given on my first visit to the majestic continent was at jo'burg bus station by a zimbabwean , 'never trust and nigerian and you will be fine - welcome to africa'

Equally disliked in Africa are chinese engineers.