I'm quoting myself to highlight my stupidity.
Originally Posted by Slug
That doesn't look like the stock Sony lockscreen
Of course it's not.... it's not ANY lockscreen - this is standard behaviour in JB when you drag up from the Home button, even in third-party launchers such as Nova. Which I discovered when I tried it. Doh!
Sorry for the misinformation, darkfly. Afaik
there's no way to alter this.