There is a scam on some borders going into Zambia, some require a yellow fever vaccination certificate even when officially it is not required (depending on where you have come from).
They threaten to send you back unles of course an agreement can be made <img src="[
www.africaguide.com]] Its worst on the Zambia - Chipata border with Malawi.
Generally they only want to know how much foreign money you have got because of the black market.
If you are going to change money on the black market you should take this into consideration when you initially declare your amounts going in and when you again declare going out as they may want official change receipts for any differences.
But I personally have never been asked for them.
Also a regular poster here Matz L Risberg travels extensively in Africa by train, you may like to read his posts. Just go to the forums search page put his name in to keywords, select author field, all forums, last 1 year, and you`ll see them all.
Hope that helps..
Phil J
moderator