VXI11 Installation , rpc/rpc.h error

[mcoliver007]

C:> gem install vxi11-0.1.3.gem
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing vxi11-0.1.3.gem:
ERROR: Failed to build gem native extension.
C:/cp/od/ruby/1.9.3-p327/bin/ruby.exe extconf.rb
creating Makefile
make
generating vxi11-i386-mingw32.def
compiling clnt_find_services.c
In file included from clnt_find_services.c:66:0:
clnt_find_services.h:69:21: fatal error: rpc/rpc.h: No such file or directory
compilation terminated.
make : ***[clnt_find_services.o] error 1

---

Do you think I need to install depencies before installing VXI11 ?

-Thanks for your time-