[snapshot 20041022] tools/hugs-package doesn't know X11 include dir

$ ./configure --prefix=$HOME/inst/hugs-snapshot
[...]
checking for X... libraries /usr/X11R6/lib, headers /usr/X11R6/include
[...]
*** NOW DO: make ; make install
************************************************
$ make
[...]
make[1]: Entering directory `/udd/f/fool/hugs98-20041022/libraries'
cd ..; libraries/tools/convert_libraries fptools hugsdir
[...]
Converting Graphics/X11/Types
In file included from Types.hsc:790:
fptools/libraries/X11/include/HsXlib.h:13: X11/X.h: No such file or directory
fptools/libraries/X11/include/HsXlib.h:14: X11/X.h: No such file or directory
fptools/libraries/X11/include/HsXlib.h:15: X11/Xlib.h: No such file or directory
fptools/libraries/X11/include/HsXlib.h:16: X11/Xatom.h: No such file or directory
fptools/libraries/X11/include/HsXlib.h:17: X11/Xutil.h: No such file or directory
fptools/libraries/X11/include/HsXlib.h:21: X11/keysymdef.h: No such file or directory
libraries/tools/hugs-package: hugsdir/packages/X11/Graphics/X11/Types_hsc_make: not found
rm: hugsdir/packages/X11/Graphics/X11/Types_hsc_make: No such file or directory
[... some errors omitted ...]
Compiling hugsdir/packages/X11/Graphics/X11/Xlib/Screen.hs
runhugs: Error occurred
ERROR "hugsdir/packages/X11/Graphics/X11/Xlib/Types.hs" - Module "Main" already loaded


Compiling hugsdir/packages/X11/Graphics/X11/Xlib/Window.hs
runhugs: Error occurred
ERROR "hugsdir/packages/X11/Graphics/X11/Xlib/Types.hs" - Module "Main" already loaded


make[1]: *** [../hugsdir/libraries/Hugs/Storable.so] Error 1
make[1]: Leaving directory `/udd/f/fool/hugs98-20041022/libraries'
make: *** [all] Error 2
$