This is a known issue - when files are added using Ankh, they are not really added to SVN. Many a times this has caused problems, for instance when committing later through TortoiseSvn only to find missing files, or when creating a patch.
Is there a workaround, or some plans to fix this is a future Ankh release?
Edit - to clarify, when I commit using Ankh, the files are really added. But if the commit is not done using Ankh, the files are not added (unlike other SVN operations which do carry over).