Steps to reproduce:
1. Open http://www.rsdn.ru/forum/message/2811878.aspx
2. Move the cursor to a thin blue line between message tree and message text (the darker single-pixel part of the line).
3. Try to drag up and down.
Results: The views are resized correctly, but a resize cursor never appears. It does appear in Firefox (not sure where it comes from, it looks like n-resize).
As far as I can tell, WebKit does not change the cursor to a resize cursor over frame resizers. Nothing specific to rsdn.ru or the fact that it stylizes the resizers.
Indeed - when I saw the n-resize cursor in Firefox, I assumed that it was a site weirdness. Turns out it Fierfox's.
Please ignore my last post (if it got posted) - the system changed the bug item when I logged in. I had selected the original, and correct, bug 16381 from my mail program.
*** This bug has been marked as a duplicate of 18477 ***