how to extract start time and end time from the CLOCK: property

[Seweryn Kokot <s.kokot@po.opole.pl>]

I would like to have a list of actions with starting and ending times
and with duration.

Now I have the column view as follows

#+BEGIN: columnview :hlines 1 :id global
| Action         | start - end,  duration                                  | duration |
|----------------+---------------------------------------------------------+----------|
| * 17-08-2008   |                                                         |    3:38  |
| ** DONE task1  | [2008-08-17 nie 09:03]--[2008-08-17 nie 10:04] =>  1:01 |    1:01  |
| ** DONE task2  | [2008-08-17 nie 10:05]--[2008-08-17 nie 10:35] =>  0:30 |    0:30  |
#+END:
#+COLUMNS: %25ITEM(Action) %55CLOCK(start - end,  duration) %8CLOCKSUM(duration)

but I would like something like this

#+BEGIN: columnview :hlines 1 :id global
| Action         | start  | end    | duration |
|----------------+--------+--------+----------|
| * 17-08-2008   |        |        |    3:38  |
| ** DONE task1  |  09:03 |  10:04 |    1:01  |
| ** DONE task2  |  10:05 |  10:35 |    0:30  |
#+END:
#+COLUMNS: %25ITEM(Action) %8CLOCK[start] %8CLOCK[end] %8CLOCKSUM(duration)

In other words it would be nice to extract starting time and ending time
from the time range in the CLOCK property so that it would be possible
to insert them in two separate columns in a column view and in a dynamic
block.

Any ideas?

regards,
Seweryn Kokot