Mainly tested on:
  Box
    - Pentium 166MHz PC.
  OS
    - Linux 2.2.17
  Make
    - GNU Make 3.79.1
  C compiler
    - GCC 2.95.2
  Ruby
    - ruby 1.6.2 (2000-12-25) [i586-linux]
    - ruby 1.7.0 (2001-01-29) [i586-linux]
  Gtk+
    - GTK+-1.2.8
