Safari 4.0.3 download "sa.aspx" files automatically

After upgraded to the new Safari v4.0.3, when load in some sites, they'll always download some "sa.aspx" files automatically, one reloads(refresh) one downloads, like "sa.aspx, sa-1.aspx, sa-2.aspx....", that's real big fat trouble!!!
Safari 4.0.2 and firefox has no same trouble, and I never seen that before.