Drag / Mouse Out, Firefox Problem

So I’m looking for a solution on the whole Firefox / ‘release outside’ problem with AS3. I’m using the method that Senocular posted:

That works great in Flash, Safari and other browsers but for some reason, not Firefox.

I’ve searched everywhere for a solution but can’t seem to find anything on it other than this: http://www.justsuppose.com/2007/06/as3flash-9firefox-mouse-capture-bug.html

…which seems to be a dead link now.

Has anyone found a fix or work around for this problem?