The S3 is only a little bit diff. than the S1.
How close are you? Shooting at the wide end or telephoto end? (been my experience that the macro is better at the wide end)
Like Craig said, you may have to activate the macro mode to "unlock" that area of focusing. But the problem arises because when you are shooting that close, even with manual focus, your depth of field is soooooooooooooooo narrow.
This I got with my S1, but I wasn't near them. It's a crop.
<img src="http://www.themeparkphotos.us/cpg140/albums/uploads/052307/B/IMG_0939crop.jpg" />