Diplomatic Passport - why was Dr. Mumba singled out?

The Mumba for President Media Campaign Team have responsded to the The Times of Zambia article about the public row over the diplomatic passport.

Under the Chiluba administration, diplomatic passports were issued to several ministers and pastors given that they were considered “Ambassadors” representing Zambia in the global arena whenever they travel abroad.

We see nothing wrong with that. What we take issue with is the way in which the Mwanawasa administration went after Dr. Mumba in regards to his possession of a diplomatic passport. Dr. Mumba informed the Ministry of Home Affairs that he would return his diplomatic passport on returning to Zambia which he has done. What was the need to blow this non-issue and make such a public hoop-la about it unless it was politically motivated?

This clearly shows that the Minister of Home Affairs was indulging in petty politics.