Dictionary within a dictionary?

Hi there (again and again and again.. lol and expect much more greetings soon) :P

Anyways im having problems initialising a dictionary within a dictionary. Ive made sure that my spaces are included :P , but the compilor seems to say otherwise. Something about not being able to convert ..... If im declaring this wrong, then please do tell. My aim is to have a for each key the value will have its own dictionary as well.

Heres what i have so far.

 import System.Collections.Generic;
 
 private var componentsExtracted:Dictionary;
 
 
 function Start() 
 {
     componentsExtracted = new Dictionary.<GameObject,Dictionary.<Component,float> >();
 }