[PD] ff on os x

[w.kosma at gazeta.pl]

hello,

i new on pd and it`s my 1st post,
forgive if this topic have been discussed here already, i couldn`t
find solution in docs etc,

i want to set up ff object to use force feedback on mac os.x.2.8
pd sees externals (i put it in extra folder), if i try to use some 
objects:

ff-gain 0 0.5
... couldn't create
ff-gain.pd 1 0 2 0 (message->text) connection failed
error: ff-gain: can't load abstraction within itself

how i can deal with this stuff, do i need any extra drivers,
do you have any example patches for using ff?
what kind of devices i can use (hid?)?

thanks for any help,
wojciech kosma