Edubuntu's desktop task is edubuntu-desktop-gnome, not edubuntu-desktop.

debian/changelog

@@ -1,7 +1,11 @@
 livecd-rootfs (0.96) UNRELEASED; urgency=low
 
+  [ Loïc Minier ]
   * Append ${SUBARCH:+-$SUBARCH} to LOG filename for consistency.
 
+  [ Colin Watson ]
+  * Edubuntu's desktop task is edubuntu-desktop-gnome, not edubuntu-desktop.
+
  -- Loïc Minier <loic.minier@ubuntu.com>  Wed, 02 Sep 2009 09:23:59 +0200
 
 livecd-rootfs (0.95) karmic; urgency=low

livecd.sh

@@ -190,7 +190,7 @@ Flags: seen
 	    LIVELIST="language-support-en kubuntu-netbook-live^ laptop-detect casper lupin-casper"
 	    ;;
 	edubuntu|edubuntu-dvd)
-	    LIST="$LIST minimal^ standard^ edubuntu-desktop^"
+	    LIST="$LIST minimal^ standard^ edubuntu-desktop-gnome^"
 	    LIVELIST="edubuntu-live^ laptop-detect casper lupin-casper"
 	    ;;
 	xubuntu)