How to apply longtable onto a clocktable?

["Sebastien Vauban" <sva-news-D0wtAvR13HarG/iDocfnWg@public.gmane.org>]

Hello,

For time-reporting purpose, I need to use `longtable' for my work table, as it
becomes way too long (over one page).

However,

  #+attr_latex: :environment longtable :float nil

seems completely ignored in that case. Hence, the results is a `tabular'
inside a `table' float...

Here an ECM (where the table is not so long).

--8<---------------cut here---------------start------------->8---
#+TITLE:     ECM Prestas
#+OPTIONS:   H:4 num:t toc:t

* Tasks

Some tasks with CLOCK lines.

** Design

*** TODO Do this
    :LOGBOOK:
    CLOCK: [2013-06-19 Wed 09:00]--[2013-06-19 Wed 10:11] =>  1:11
    :END:
    :PROPERTIES:
    :Effort:   2:00
    :END:

** Develop

*** TODO Do that
    :LOGBOOK:
    CLOCK: [2013-06-19 Wed 10:00]--[2013-06-19 Wed 12:22] =>  2:22
    CLOCK: [2013-06-20 Thu 10:01]--[2013-06-20 Thu 12:35] =>  2:34
    :END:

* Reporting

** Summary

#+TBLNAME: prestasTotal
#+attr_latex: :environment longtable :float nil
#+BEGIN: clocktable :maxlevel 4 :scope file :block 2013-06 :lang "en" :narrow 80! :indent t
#+CAPTION: Clock summary at [2013-07-02 Tue 12:16], for June 2013.
| Headline            | Time |      |      |
|---------------------+------+------+------|
| Total time          | 6:07 |      |      |
|---------------------+------+------+------|
| Tasks               | 6:07 |      |      |
| \__ Design          |      | 1:11 |      |
| \_____ TODO Do this |      |      | 1:11 |
| \__ Develop         |      | 4:56 |      |
| \_____ TODO Do that |      |      | 4:56 |
#+END:
--8<---------------cut here---------------end--------------->8---

How can I set the desired table environment?

Best regards,
  Seb

-- 
Sebastien Vauban