Description of problem:
gnome-session-properties fails to save modifications to command line in a start-up job. 


Version-Release number of selected component (if applicable):
gnome-session-2.28.0-18

How reproducible:
Every time.

Steps to Reproduce:
1. Open gnome-session-properties. Create a new start-up (fill all 3 fields) job and save it. Close gnome-session-properties.
2. Re-open gnome-session-properties. Open the job created in step 1. Verify it has the same command line as entered at step 1. Modify the command line and save the chages. Close gnome-session-properties.
3. Re-open gnome-session-properties. Open the job created at step 1. The command line is still the one, set in step 1 (and not the one, modified in step 2).

Actual results:
Modification to comamnd line are not saved.

Expected results:
Modification to comamnd line should be saved.

Additional info:
There are other issues with this component too, e.g. if you delete a job and try to create the same, it will not be saved at all. This is rather confusing and needs attention.