I use Xfce all the time at home and I rdesktop into loads of different computers. Over time I have created many desktop entries for rdesktop connections to many different computers.
E.g.
[Desktop Entry]
Version=1.0
Type=Application
Encoding=UTF-8
Exec=rdesktop -d ; -z -u -g 1670x1025 -k de
Icon=chardevice
StartupNotify=false
Categories=Network
Name=RDesktop(hostname)
Comment=RDesktop(hostname)
Each entry I created needed to be created in the ~/.local/share/applications
directory. These are then automatically loaded and added to the Network
sub menu. (The list of main categories is listed here)
I started to get problems after adding 12+ desktop entries to the Network menu. With the standard Network entries and my custom rdesktop entries it was getting very tall and messy.
I then started to look into if I could move the rdesktop commands into its own submenu separating them out.
I found that I could make general changes to the menu layout via the menu file. On my distribution its located ~/.config/menus/xfce-applications.menu
Simply create a new submenu
and include this in the main Layout section
exo-terminal-emulator.desktop
exo-file-manager.desktop
exo-mail-reader.desktop
exo-web-browser.desktop
RDesktop
Settings
xfhelp4.desktop
xfce4-run.desktop
xfce4-about.desktop
xfce4-session-logout.desktop
The rdesktop.directory entry in the submenu points to a file in the .local/share/desktop-directories/rdesktop.directory
desktop file. This mainly defines the menu icon and a few other things. It looks like this
[Desktop Entry]
Version=1.0
Type=Application
Encoding=UTF-8
Exec=rdesktop
Icon=chardevice
StartupNotify=false
Categories=X-XFCE;RDesktop
Name=RDesktop
Comment=RDesktop
I then updated the individual desktop files to use the new group.
I.e Categories=Network;RDesktop
[Desktop Entry]
Version=1.0
Type=Application
Encoding=UTF-8
Exec=rdesktop -d ; -z -u -g 1670x1025 -k de
Icon=chardevice
StartupNotify=false
Categories=RDesktop
Name=RDesktop(hostname)
Comment=RDesktop(hostname)
Dont forget to read http://wiki.xfce.org/howto/customize-menu too.