In working with org-mode's taskjuggler exporter, I have noticed that it does not support the attributes chargeset and charge in taskjuggler 3. These attributes are necessary to use taskjuggler's cost estimating functions. I am not much of a coder, but I have tried my hand at a patch.

commit 15b522901ff0dcd8a581ad55cd4bf4c3688908ad
Author: Bill Day <williamson.day@gmail.com>
Date:   Sun Aug 26 16:58:32 2012 -0400

    Modified taskjuggler to add chargeset and charge

diff --git a/lisp/org-taskjuggler.el b/lisp/org-taskjuggler.el
index aa645d2..2418654 100644
--- a/lisp/org-taskjuggler.el
+++ b/lisp/org-taskjuggler.el
@@ -659,7 +659,7 @@ org-mode priority string."
     '(account start note duration endbuffer endcredit end
             flags journalentry length maxend maxstart minend
             minstart period reference responsible scheduling
-            startbuffer startcredit statusnote)))
+            startbuffer startcredit statusnote chargeset charge)))
     (insert
      (concat
       "task " unique-id " \"" headline "\" {\n"

--
Bill Day
williamson.day@gmail.com