Laeuft das hfs+ Modul im Kernel oder im user space? Wenn es im user space laeuft, liegt es evtl. daran.
http://ubuntuforums.org/showthread.php?p=7060899 schrieb
... HFS+ needs to be compiled into the kernel to be exported via nfs-kernel-server. The other option is to export it via nfs-user-server. It is not as efficient as the nfs-kernel-server because it is in user space but at least you should be able to export your HFS+ partition without having to recompile your kernel.