If you are talking about the scrollbar that automatically appears on a div
with overflow: scroll
(or auto
), then no, that's still a native scrollbar rendered by the browser using normal OS widgets, and not something that can be styled(*).
Whilst you can replace it with a proxy made out of stylable divs and JavaScript as suggested by Matt, I wouldn't recommend it for the general case. Script-driven scrollbars never quite behave exactly the same as real OS scrollbars, causing usability and accessibility problems.
(*: Except for the IE colouring styles, which I wouldn't really recommend either. Apart from being IE-only, using them forces IE to fall back from using nice scrollbar images from the current Windows theme to ugly old Win95-style scrollbars.)