Installation problem uconv-0.4.12. plz help

Hi guys,

I need to install Unicode Conversion Module for Ruby version 0.4.12 by
Yoshida Masato.I have followed the commands of the link inmy windows

but when I use the command “ruby extconf.rb” it create “MakeFile”
but when I use “make” command it fails…‘make’ is not recognized as a

so I can not install Uconv. I use ruby 1.8.5 (2006-12-25 patchlevel 12)

How can i solve the problem? Any other way to convert Unicode string
to Japanese string.