Has the wording changed for the visa requirement?
Delta.com now returns the following:


TWOV (Transit Without Visa):
Visa required, except for Holders of onward tickets for a max.

transit TIRULES/R32 time of 6 hours.
- The onward carrier is required to report the onward booking
to the Immigration Authorities.

This last line makes it a bit problematic if you are flying in on a different ticket to the one you are flying out on as would be the case for everyone commencing an xONEWx from Sudan

And moa999 as long as the following link is still accurate then not everyone requires an exit visa point c) being the most relevant

http://www.unhcr.org/refworld/pdfid/469e20832.pdf

4) The following persons shall not require an exit visa in order to leave the
New Sudan:-
a) holders of foreign diplomatic passports.
b) officials of the United Nations and other recognized
International bodies.
c) visitors staying in the New Sudan for not more than three
months.