diff --git a/ext/v8/build.rb b/ext/v8/build.rb
index 943645e..b713794 100644
--- a/ext/v8/build.rb
+++ b/ext/v8/build.rb
@@ -2,10 +2,13 @@
 LIBV8_COMPATIBILITY = '~> 3.11.8'
 
 def have_rubygem_libv8?
+  require 'rubygems'
   gem 'libv8', LIBV8_COMPATIBILITY
   return true
 rescue Gem::LoadError
   return false
+rescue LoadError
+  return false
 end
 
 def build_with_system_libv8