Hi, I paddled the entire length of the zambezi in 2009/2010, unsupported, including the Angolan section which has to date stopped other attempts. i paddled a total of 3500km in 77 days using sea kayaks.
one issue i would like to warn you about is crocs. we had many close encounters with them especially on the lower sections of the river in mozambique and zimbabwe. i consider myself very fortunate to have made the sea at chinde in one piece it was so bad!
if you need any help/info let me know.