CellTree: Horizontal Scrollbar impossible?

[opn]

I hope it's not impossible right now to get a horizontal scrollbar
with a cellTree growing large in x-direction, but I just can not find
a solution.
The problem is that the cellTree automatically crates something like:
<div style="overflow: hidden;">
...
</div>

I can not find a way to disable this.

When i disable all these manually with, for example, firebug, my tree
begins to be scrollable.

Now the question:

Did anyone implement successfully a horizontal scrollable CellTree .

[Jeff Larsen]

You can always walk up the dom and change the div. It is kinda hacky, but it will work. 

[Derek]

The get showcase has horizontal scrolling.
http://gwt.google.com/samples/Showcase/Showcase.html#!CwCellSampler