Problems trying to "make" it

Hi!
I’m new here. My name is Alexandre and this is my first post.
Well, I bought a book (here in Brazil, where I live) about Ruby and
tryed to follow the steps to add gtk2 interface.
I downloaded the ruby-gtk2 on http://ruby-gnome2.sourceforge.jp to the
root folder (I use Suse linux). Then, I typed “ruby extconf.rb” … :

linux-8ky4:~/ruby-gtk2-0.16.0 # ruby extconf.rb

extconf.rb: Entering directory glib' checking for GCC... yes checking for rb_define_alloc_func()... yes checking for rb_block_proc()... yes checking for new allocation framework... yes checking for attribute assignment... yes checking for gobject-2.0... yes checking for gthread-2.0... yes checking for G_PLATFORM_WIN32... no checking for g_spawn_close_id()... no checking for g_thread_init()... yes checking for g_main_depth()... yes checking for g_listenv()... yes checking for rb_check_array_type()... yes checking for rb_exec_recursive()... no checking for yarv.h... no creating glib-enum-types.c creating glib-enum-types.h creating Makefile extconf.rb: Leaving directory 'glib' extconf.rb: Entering directory gdkpixbuf’
checking for GCC… yes
checking for rb_define_alloc_func()… yes
checking for rb_block_proc()… yes
checking for new allocation framework… yes
checking for attribute assignment… yes
checking for gdk-pixbuf-2.0… yes
checking for G_PLATFORM_WIN32… no
checking for gdk_pixbuf_set_option()… yes
checking for gdk-pixbuf/gdk-pixbuf-io.h… yes
checking for cairo… yes
checking for gdk-2.0… yes
checking for rb_cairo.h… no
creating Makefile
extconf.rb: Leaving directory ‘gdkpixbuf’
extconf.rb: Entering directory pango' checking for GCC... yes checking for rb_define_alloc_func()... yes checking for rb_block_proc()... yes checking for new allocation framework... yes checking for attribute assignment... yes checking for pango... yes checking for G_PLATFORM_WIN32... no checking for pango_layout_iter_get_type()... yes checking for pango_layout_set_ellipsize()... yes checking for pango_layout_get_font_description()... yes checking for pango_render_part_get_type()... yes checking for pango_attr_strikethrough_color_new()... yes checking for pango_attr_underline_color_new()... yes checking for pango_glyph_item_free()... yes checking for pango_attr_iterator_get_attrs()... yes checking for pango_itemize_with_base_dir()... yes checking for pango_font_family_is_monospace()... yes checking for pangocairo... yes checking for rb_cairo.h... no creating rbpangoversion.h creating Makefile extconf.rb: Leaving directory 'pango' extconf.rb: Entering directory atk’
checking for GCC… yes
checking for rb_define_alloc_func()… yes
checking for rb_block_proc()… yes
checking for new allocation framework… yes
checking for attribute assignment… yes
checking for atk… yes
checking for G_PLATFORM_WIN32… no
checking for atk_action_get_localized_name()… yes
checking for atk_hyperlink_is_inline()… yes
checking for atk_object_add_relationship()… yes
checking for atk_object_remove_relationship()… yes
checking for atk_component_get_layer()… yes
checking for atk_component_mdi_zorder()… no
checking for atk_hyperlink_is_selected_link()… yes
checking for atk_text_get_bounded_ranges()… yes
checking for atk_role_get_localized_name()… yes
checking for atk_text_clip_type_get_type()… yes
checking for atk_text_free_ranges()… yes
creating rbatkversion.h
creating Makefile
extconf.rb: Leaving directory ‘atk’
extconf.rb: Entering directory `gtk’
checking for GCC… yes
checking for rb_define_alloc_func()… yes
checking for rb_block_proc()… yes
checking for new allocation framework… yes
checking for attribute assignment… yes
checking for gthread-2.0… yes
checking for gtk±2.0… yes
checking for G_PLATFORM_WIN32… no
checking for target… x11
checking for gtk_plug_get_type()… yes
checking for gtk_socket_get_type()… yes
checking for pango_render_part_get_type()… yes
checking for XReadBitmapFileData()… yes
checking for X11/Xlib.h… yes
checking for XGetErrorText()… yes
checking for gtk±unix-print-2.0… yes
checking for gtk_print_unix_dialog_get_type()… yes
checking for gtk_print_job_get_type()… yes
checking for gtk_printer_get_type()… yes
checking for gtk_page_setup_unix_get_type()… no
checking for cairo… yes
checking for rb_cairo.h… no
creating Makefile
extconf.rb: Leaving directory ‘gtk’


Target libraries: glib, gdkpixbuf, pango, atk, gtk

Done.
linux-8ky4:~/ruby-gtk2-0.16.0 #

=====================================================================
… and then “make”. But the system returned this to me:

linux-8ky4:~/ruby-gtk2-0.16.0 # make

(these are the last lines):
.
.
.
rbgtktreeiter.c: In function ‘rbgtk_register_treeiter_set_value_func’:
rbgtktreeiter.c:23: error: argument ‘gtype’ doesn’t match prototype
rbgtk.h:118: error: prototype declaration
make[2]: *** [rbgtktreeiter.o] Error 1
make[2]: Leaving directory /root/ruby-gtk2-0.16.0/gtk/src' make[1]: *** [all] Error 2 make[1]: Leaving directory /root/ruby-gtk2-0.16.0/gtk’


SUCCEEDED: gdkpixbuf pango atk
FAILED: glib gtk

Done.
linux-8ky4:~/ruby-gtk2-0.16.0 #

=====================================================================

Could anyone help me? If the gtk2 is very hard to use, what GUI can I
use?

Thank you,
Alexandre.