As per Gambit's request:
First of all, copy the entire object and duplicate it.
Once you've done this, select it and assign a single colour so all the vectos will be colored the same.
Expand the object (Object -->Expand) by select only "object" option.
Once this is done, it's time to trasform it into one single vector by clicking the "Combine" button on the dedicated window tool.
Ok, now create an ellipse (or whatever shape the lightsource will need to be) filling it with a gradient circular effect (I.e. just like the one you can see marked in green), and assign it a special transparency setting "Multiply".
Put the gradiented ellipse on the back of the Red vector copy.
Select them altogether, and select "create clipping mask" (from object menu).
You'll now have your toy done, as you can see we have created a pixel perfect reproduction of the original vector but with a special lighting property (which can be altered as any gradient, of course!).
Let's just place it on top of our shape and.. Congratulations! ^^