I lived in Tanzania for a while and drove a Zimbabwe-registered truck around there for over a year. But that was about ten years ago. However, I still spend a great deal of time in Africa and I seriously doubt that Tanzania, which is not a wealthy country, could afford to give foriegn or UK-owned vehicles a tracking device and staff a center to monitor it. More importantly, there is a massive amount of vehicle traffic across TZ's borders and while reasonably efficient by African standards, border officials are not going to have the time to check what route you took across the country. Like most of East Africa, tourism is a big part of the economy and it would be really dumb to harass travellers. If anything, this sounds like the Chinese, who have a persuasive influence, trying to sell the government something they don't need to make a few bucks.
So, if their is such a programme, it will sort of function for about a week and then fade into pointlessness. I plan on going back for a south and east Africa drive in a couple of years in my UK registered 110 and will not be worrying about a tracker, even if they give me one...which I seriously doubt. I know all this sounds a bit harsh, but I do know Africa pretty well. TZ has started to have a few problems with Islamic extremism and this may an attempt to 'protect' foriegners who wander away from relatively well secured safari areas and other tourist locations. I would check with the British High Commission in Dar es Salaam and see what they have to say.
Hope that helps...
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