gear box leak

Hi guys,
Got a bit of a mystery on my hands. I have a 1987 110 with the 2.5td engine and origional gearbox in it. i have noticed a small amount of atf dripping off the bottom of the gearbox. It appears to be leaking from the top and running down the side then dripping off. I cant see where it is leaking from but whenever i look under there there is always a drip on the bottom of the box. Any ideas of where it may be coming from?

Thanks

are we psychic?

if you cant see where its comin from and you have the landy how can we tell without any pics?