yeh sure, please note that im using ver 7 and dont know if the process differs inearlier versions.

make sure your character has a plane below it.

create a new render layer

select all objects (no lights) and place in the render layer

select this layer

hold the right mouse button over the layer, > presets > occlusion.

if it has worked correctly everything should go black

render away.

you can increase the quality of the render by selecting the sphere icon on the render layer, select the arrow next to out color and increase samples, 32 or 64 should be adequate.

any problems, let me know..hope this helps.