How do you remove diesel oil stains on Leather shoes?

I was very upset about my gorgeous leather boots ending up with a solid drop of diesel on them. The corn starch removed it brilliantly. I couldn't get the friction strong enough to get warm, so I just rubbed the spot thouroughly and solidly about 5 times for about a minute each time, using clean corn starch each time and brushing the starch off with a soft clean dry brush between each time.

It worked a treat :)