Please describe the problem:
If I create a fixed duration task that lasts 1d, it only lasts 7h in the planner data.  The duration of the task as displayed in the task view is 1d, but it's really only 7h.  If you create a test-task with a single fixed-duration sub-task which lasts 1d, you'll see that the parent task's duration is 7h in the task view.  

If I create a fixed duration task that lasts 2d, it only lasts 1d6h.  3d, 2d4h, etc...  It seems that fixed duration tasks lose 1h/day of duration.  This is a big problem, as it results in inaccuracies in the duration of the overall schedule.

Another way to see this discrepancy is to create a large fixed-duration task (10d for example), and click and unclick the "fixed duration" button in the "Edit Task" dialog.  You'll see the graphic of the duration shrink and un-shrink to reflect the discrepancy in hours.

Steps to reproduce:
1. Create a task
2. Create a fixed-duration sub-task of the task created in step 1 which lasts 1d
3. Go to Tasks view and notice the duration of the top-level task.  It's 7h...


Actual results:
I end up with fixed-duration tasks that are inaccurate in duration in my schedule.

Expected results:
The duration of a 1d fixed-duration task is 1d, not 7h.

Does this happen every time?
Yes.

Other information:
A workaround is to add 1h for each day of duration for fixed-duration tasks.  For example, make a 1d task 1d1h.  A 2d task 2d2h, etc...  This workaround is aweful, however, as when this bug is fixed, the entire schedule will be thrown off kilter.