I don't think keeping locally grown food prices and employment up are the key issues when the harvests are failing. The argument of giving them money instead of food and let them handle it themselves is not bad per se, the food would still not come from Zambia or the other countries though. While food aid can act as a domestic subsidy for the country giving it, that doesn't mean that it inherently bad, just that the donor country gets something out of it as well.
The following are some details from the famine of 2002:
Hundreds have already died in Malawi and the threat of famine looms large in Zambia, Zimbabwe, Angola, Mozambique, Swaziland, and Lesotho.
Crops have failed due to droughts and floods. Attempts to deal with the problem have been hampered by political chaos and the inadequate infrastructure in the most affected places.
The World Food Programme (WFP) said that southern Africa needs 1.2m tonnes of food to help it through the year. The EU and the US are helping, but the main problem is effective delivery.