seems like the following diff solved the problem, needs to ensure that it doesn't break anything else.

diff --git a/config/initializers/puppet.rb b/config/initializers/puppet.rb
index c3031a8..5a8ae6c 100644
--- a/config/initializers/puppet.rb
+++ b/config/initializers/puppet.rb
@@ -2,3 +2,7 @@ class Resource < Puppet::Rails::Resource
 end
 class SourceFile < Puppet::Rails::SourceFile
 end
+class ResourceTag < Puppet::Rails::ResourceTag
+end