I'm getting strange artifacts that look like unfilled shadows near the horizon out to sea

and
I'm running an AMD (ATI) 4950 2GB driver 8.831.2.0 (driving 1280x1024!), Win 7-64, 6 GB RAM, Kingston SSD, Intel Q9550 at stock 2.83 GHz.
Apart from that, post patch, it's now running fine! 50-60 fps over land, much less stuttering, grass, shadows, roads on, buildings & trees medium, all else at high.
56RAF_phoenix