diff --git a/lib/puppet/face/yardoc.rb b/lib/puppet/face/yardoc.rb
index bb52f84..ce6f09c 100644
--- a/lib/puppet/face/yardoc.rb
+++ b/lib/puppet/face/yardoc.rb
@@ -14,6 +14,10 @@ Puppet::Face.define(:yardoc, '0.0.1') do
         raise RuntimeError, "The 'rgen' gem must be installed in order to use this face."
       end
 
+      if RUBY_VERSION < '1.9' && !Puppet.features.require_relative?
+        raise RuntimeError, "The 'backports' gem must be installed in order to use this face under Ruby 1.8.7."
+      end
+
       # The last element of the argument array should be the options hash.
       #
       # NOTE: The Puppet Face will throw 'unrecognized option' errors if any
diff --git a/lib/puppet/feature/require_relative.rb b/lib/puppet/feature/require_relative.rb
new file mode 100644
index 0000000..2a677f0
--- /dev/null
+++ b/lib/puppet/feature/require_relative.rb
@@ -0,0 +1,4 @@
+require 'puppet/util/feature'
+
+# Support require_relative under Ruby 1.8.7.
+Puppet.features.add(:require_relative, :libs => ['backports/1.9.1/kernel/require_relative'])