Here is a list of bundled XEmacs' packages : (note that some are MULE-only)

            ada	           apel	         auctex           bbdb
          build	      c-support	           calc       calendar
        cc-mode	      clearcase	         cookie          crisp
          debug	     dictionary	          dired     docbookide
        ecrypto	         edebug	          edict          ediff
     edit-utils	            edt	            efs        egg-its
          eieio	           elib	         emerge         eshell
            ess	          eterm	           eudc       footnote
          forms	     frame-icon	     fsf-compat          games
          gnats	           gnus	   haskell-mode hm--html-menus
        ibuffer	        idlwave	          igrep          ilisp
         ispell	            jde	    latin-unity           leim
          liece	         locale	         lookup       mail-lib
      mailcrypt	            mew	           mh-e           mine
     misc-games	       mmm-mode	      mule-base       mule-ucs
      net-utils	          ocaml	       os-utils             pc
        pcl-cvs	      pcomplete	     prog-modes       ps-print
          psgml	     psgml-dtds	         reftex          rmail
           sasl	         scheme	       semantic           sgml
      sh-script	          sieve	            skk         slider
       sml-mode	      sounds-au	     sounds-wav       speedbar
        strokes	      supercite	        texinfo     text-modes
       textools	           time	             tm       tooltalk
            tpu	          tramp	             vc          vc-cc
           vhdl	   view-process	          viper             vm
             w3	    xemacs-base	   xemacs-devel         xslide
   xslt-process	         zenirc
