I'm on a HP ZE4900 laptop, and the trackpad will not scroll on any page.
See also bug 14227.
I've tested the problem in the latest Webkit on HP nx9020 with Synaptics touchpad drivers installed. Scrolling works fine here. Ricky, could you check if the problem still exists in your system?
Resolved as WORKSFORME. Ricky, feel free t reopen the bug if you still experience this problem.