[O] taskjuggler - using gaplength or gapduration

[frank]

One issue that I am having is regarding gaplength and gapduration for 
tasks.  Under the TJ3 syntax, the command would be
" depends !!PHII {gapduration 7w} ".

I added gaplength and gapduration under ' Org Taskjuggler Valid Task 
Attributes ' and added the following in my org-mode file:

*** PSF
    :PROPERTIES:
    :Task_id: PSF
    :depends: PHII
    :gaplength: 7w
    :duration: 10d
    :END:

The resulting export comes out:
    depends !!PHII
    duration 10d
    gaplength 7w

which is incorrect.  What am I doing wrong.

Frank