In Samba 3.3 we log every access that was denied to a share due to a valid users or similar setting with debug level 0. In 3.2, we did not do this. I'd propose fix this in the next version of Samba 3.3. These messages can be particularly annoying, as they always end up in syslog.
Created attachment 4109 [details] patch
Patch looks fine to me: +1
+1
Patch is upstream and will be included in 3.3.5. Closing out bug report.