Anchor Tag Problems w/ DHTML-CSS Scrollbar

Is it possible to include an internal anchor tag reference within a DHTML/CSS scrollbar?

In this example

http//www.unifiedmobility.com/scroll.html

When scrolling to the bottom of the scroll frame, the DHTML/CSS <span> environmnet will not allow me to internally hyperlink back to the top of the page using a standard <a href="#top"> syntax anchor link.

Any help is greatly appreciated.