FolderItem SaveInfo problem

Given a FolderItem “f” that does not exist but is not Nil (that is, it’s “promised”), this does not work, on Mac 10.4 and the latest Xojo.

FileStr = f.SaveInfo(Nil, FolderItem.SaveModes.Full)
f = FolderItem.FromSaveInfo(FileStr)

f is at this point Nil, and when I look at the contents of FileStr, it’s way shorter than it usually is (like when f represents a file that exists). f should be preserved.

Is this a bug? The documents don’t say anything about SaveInfo with folder items that don’t exist. And this works on RS2011r3 on OSX 10.6.