Does scope not work on parameters?

[Russ]

Hi, I've been playing around with having classes allocated on the 
stack. I am using the scope keyword for local variables. I 
assumed that the scope modifier for function parameters was 
designed to prevent these from escaping, but the code below 
doesn't show any errors. Is there some newer feature I should be 
using? Thanks.

import std.stdio;

class Foo
{
}

class Bar
{
	Foo foo;
}

void doSomething(scope Foo z, Bar b)
{
	b.foo = z;
}

void main()
{
	Bar b = new Bar;
	scope foo = new Foo;
	doSomething(foo, b);
}