Audible book doesn't show in Audiobooks

[fetalsono]

I have a 3GS and have 11 books from audible.com on my iPhone. I recently added another to iTunes and checked it and then synced the phone. When I went into the iPod area and then into Audiobooks, the book was not there. I synced again and still no change. I tried looking for the author or title in the iPod area and couldn't find it. I then did a search for the book using the search function on the iPhone, and the book was on my iPhone and played normally, . I have plenty of memory so that is not the issue. I am puzzled as to where this book is on my iphone. I ideally would like it to be in the Audiobooks section. I have never had a problem like this before. I have presently 11 audiobooks in my iPod (Audiobooks) section. Maybe there is a limit.

Thanks

Peter