I can't remember where I got this from. I found it on the web. Anyway, here is how I got rid of the stickiness of an old Nikon D70's rubber parts:
Before proceeding, make sure that you have a body cap on the camera.
Use as little of the cleaning solutions as possible to get the results that you need.
Only clean the rubber parts of the camera.
Test it on a small area of the rubber first.
First step, wipe the sticky surface with a rag that has WD40 on it.
Second step, clean the WD40 off with a rag containing rubbing alcohol.
This worked for me, but use at your own risk!