The shortut is controlled by the file ShortcutBar.DAT which is located in the C:\Program Files\Hewlett-Packard\OpenView\service desk 4.5\client\repo directory on the application server. It is copied to the clients workstation.
I have not tried this but it maybe possible to update the server copy (via the system panel) and then delete the client version. SD should then copy the server copy to the client. In theory this should work but test it first.