1. Go to bug url (though as far as I can tell, this is true for any url where there are images on the page)
2. Right-click anywhere on the page, and select Inspect Element.
3. In the web inspector, click on resources
4. Click on download.png in the left hand column
5. Right click on the image in the central pane, and select "Download image"
Image will be downloaded to default downloads folder, or a file save dialog will come up.
Tested with r32531, but same behavior also exists in Safari Version 3.1.1 (5525.18). Not sure if it is a regression from an earlier version. Tested on 10.5.2
*** This bug has been marked as a duplicate of 18147 ***