The error appears to be in the package haskell-mode.  Reassigning.

Quoting the attached DpkgTerminalLog.txt:
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-c.el...
> #<compiled-function nil "...(4)" [values t] 2>
> While compiling toplevel forms in file /usr/share/xemacs21/site-lisp/haskell-mode/haskell-c.el:
>   !! Invalid read syntax (("#"))
> >>Error occurred processing haskell-c.el:
> Invalid read syntax: "#"
>
>
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-cabal.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-cabal.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-decl-scan.el...
> While compiling toplevel forms in file /usr/share/xemacs21/site-lisp/haskell-mode/haskell-decl-scan.el:
>   !! Wrong number of arguments ((require 3))
> >>Error occurred processing haskell-decl-scan.el:
> Wrong number of arguments: require, 3
>
>
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-doc.el...
> While compiling toplevel forms in file /usr/share/xemacs21/site-lisp/haskell-mode/haskell-doc.el:
>   !! Wrong number of arguments ((require 3))
> >>Error occurred processing haskell-doc.el:
> Wrong number of arguments: require, 3
>
>
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-font-lock.el...
> While compiling toplevel forms in file /usr/share/xemacs21/site-lisp/haskell-mode/haskell-font-lock.el:
>   !! Invalid read syntax (("#"))
> >>Error occurred processing haskell-font-lock.el:
> Invalid read syntax: "#"
>
>
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-ghci.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-ghci.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-hugs.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-hugs.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-indent.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-indent.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-indentation.el...
> While compiling toplevel forms in file /usr/share/xemacs21/site-lisp/haskell-mode/haskell-indentation.el:
>   !! Wrong number of arguments ((require 3))
> >>Error occurred processing haskell-indentation.el:
> Wrong number of arguments: require, 3
>
>
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-mode.el...
> #<compiled-function nil "...(3)" [t] 2>
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-mode.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-simple-indent.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-simple-indent.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/haskell-site-file.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/haskell-site-file.elc
> Compiling /usr/share/xemacs21/site-lisp/haskell-mode/inf-haskell.el...
> Wrote /usr/share/xemacs21/site-lisp/haskell-mode/inf-haskell.elc
> Done
> emacs-install: /usr/lib/emacsen-common/packages/install/haskell-mode xemacs21 emacs-snapshot emacs23 failed at /usr/lib/emacsen-common/emacs-install line 28, <TSORT> line 7.
> dpkg: error processing xemacs21-mule (--configure):
>  subprocess installed post-installation script returned error exit status 1