+4  A: 

I think you might want to review Douglas Crockford's writing on inheritance in JavaScript. He has some in his book JavaScript: The Good Parts, and some in his lectures on YUI Theater <http://developer.yahoo.com/yui/theater/>. For distinguishing objects properties from those of the objects from which they are derived, see the hasOwnProperty() method. Crockford seems to argue that using classical inheritance in JavaScript is possible, but not the best way to go about exploiting the languages capabilities. Perhaps this will give you ideas on how to go about addressing what you're trying to accomplish. Best of luck regardless!

Crockford on Inheritance:

artlung
Thank you. :) hasOwnProperty() works like a charm.
NixNinja