Missing member

[Mizipzor]

I have some troubles with a member variable that seems to be missing
in a class. In short, heres what I do; class A is the parent class, B
inherits from A and C inherits from B (hope I used the right words
there). Now, I create an instance of C, which calls A's __init__ which
in turn creates all the member variables. Then I call C.move() (a
function defined in A), but then, one of the variables seems to have
become 'NoneType'.

The code can be found here (Ive taken away unnecessery stuff):
http://pastebin.com/875394

The exact error is (which occur on line 15 in the pasted code):
TypeError: unsupported operand type(s) for *: 'NoneType' and 'float'

Any comments are welcome. :)