indexOf a valid Key in Josephus returns -1

Here is my test:

Book book = getBook("Josephus");
assertNotNull("Josephus not available", book);

// find a key and print out it's name - this works
final String SECTION_2 = "Section 2";
Key key = book.getKey(SECTION_2);
assertEquals(SECTION_2, key.getName());

// but we can't get it's index - this returns -1
int keyPos = book.getGlobalKeyList().indexOf(key);
assertFalse("Could not get index of a valid key", -1==keyPos);

When dealing with a book having TreeKeys the top level Key returned by book.getGlobalKeyList is not a TreeKey but a KeyList which therefore does not automatically search it's children. So I wonder if SwordGenBook.global could be a TreeKey rather than a ReadOnlyKeyList.

Maybe the way it works is the way it should work but I am not sure. Now I realise what is happening I could just call indexOf on each child of the globalKeyList but I think it would be more elegant if globalKeyList.indexOf returned a key from lower down in the tree.