Fixing JavaScript

Looks like Microsoft are actually working on a fix for the circular reference memory leak in their JavaScript implementation. About time, perhaps, but I'd love to know the techy details. How do they get their JavaScript garbage collector to know what references (direct or indirect) an unknown COM object holds?

Is there going to be a separate interface that lists references? This would have to be implemented on the HTML element objects, and so would fail with ActiveX COM objects.

Perhaps the GC lists all properties of a (non-JavaScript) expando object and examines them for a known interface to indicate a JavaScript object. This would allow it to know when a circular reference was made, but it wouldn't identify if the original non-JavaScript object was referenced outside of the script engine.

It's an interesting problem.

But there goes my theory about them using the new managed JavaScript from Silverlight...