Several items of a menu disappear when moving down an item in the launcher
properties dialog. The number of items which disappear grows with the number of
"down" movements. If you move one item down only once, it's always the last but
one item which disappears. Only happens when there are more than 3 items in a
menu. Reproducible on three machines runing Xfce 4.3 on Debian.

Reproducible: Always
Steps to Reproduce:
1. create a launcher with a more than 3 items long menu
2. open the launcher properties dialog
3. take the first item of the list and move it down to the latest position
4. close the dialog
5. open the menu: several items are gone




libxml2 2.6.16
libgtk2 2.6.8
xfce4-panel 4.3.2 (SVN revision 16145)