Thanks for the feedback.
As rolify calls super in a else statement in the respond_to method (see here), I guess that socialization gem is using the same is_something? method name pattern. So any gem using the same pattern could conflict with rolify, thanks for pointing that out.
Can you try a quick fix on your setup ? change the respond_to? method to this:

def respond_to?(method, include_private = false)
  if Rolify.dynamic_shortcuts && (method.to_s.match(/^is_(\w+)_of[?]$/) || method.to_s.match(/^is_(\w+)[?]$/))
    query = self.class.role_class.where(:name => $1)
    query = self.class.adapter.exists?(query, :resource_type) if method.to_s.match(/^is_(\w+)_of[?]$/)
    return true if query.count > 0
  end
  super
end

@gitgary did you have a chance to try the workaround in my previous post ?

Hi Florent

Sorry for not responding sooner. Yes, I did try it and yes it seems to be working properly now. It certainly no longer crashes and appears ok. I plan to do a bit more detailed testing however. If I see any odd behavior, I'll be sure to post. Thanks!

@EppO Hi, it seems I'm getting the same error here, can you tell me where I have to put the override code for respond_to? thank you