when i move a file or folder to the trashcan and den open the context menu on this folder, i can select send to -> desktop (create link), but this operation is not possible. this option should not be shown which means that for files the "send to" submenu would not be shown at all since "desktop" is the only option for files. folders can still be sent to the sidepane to create shortcuts, so that should stay. (although i don't think it makes much sense to create shortcuts to folders in the trash, but that may be only my opinion.)
Fixed with revision 23824. 2006-11-11 Benedikt Meurer <benny@xfce.org> * thunar/thunar-launcher.c(thunar_launcher_sendto_idle): Do not display the "Desktop (Create Link)" sendto-action for trashed files, because symbolic links cannot be created for files in the trash. Bug #2539.