When the pointer is over the pictures from the result page <http://images.google.pt/images?q=webkit&svnum=30&hl=pt-PT&lr=&newwindow=1&safe=off&start=18&sa=N&ndsp=18>, Safari show fine, but Webkit no. See attachments.
Created attachment 12547 [details] safari show
Created attachment 12548 [details] Webkit show
Confirmed using locally-built debug build of WebKit r19127 with Safari 2.0.4 (419.3) on Mac OS X 10.4.8 (8N1037).
*** This bug has been marked as a duplicate of 11109 ***