RubyGems rack version update issue

I have a problem with my Serve set up. I ran an update of my gem files and now when I boot serve (or Sinatra) I get this error:

/Users/yannick/.rvm/gems/ruby-1.9.2-p290/gems/rack-1.3.4/lib/rack/backports/uri/common_192.rb:53: warning: already initialized constant WFKV_
/Users/yannick/.rvm/gems/ruby-1.9.2-p290/gems/bundler-1.0.21/lib/bundler/runtime.rb:31:in `block in setup': You have already activated rack 1.3.4, but your Gemfile requires rack 1.3.3. Using bundle exec may solve this. (Gem::LoadError)

I've seen a few solutions around the web and here on Stackoverflow, they all recommend to running bundle update, specify the rack version in the gem file, delete the gemfile.lock or run bundle exec.

I've tried all of them but to no avail.

As for the bundle exec command is there a difference between rack and rake. If i run bunde exec rake like in there:

You have already activated rack 1.3.2, but your Gemfile requires rack 1.2.3. Consider using bundle exec

I just get a message saying that there is no rake service running.

rake aborted!
No Rakefile found (looking for: rakefile, Rakefile, rakefile.rb, Rakefile.rb)

If I try to do a bundle exec rack, I get a no such exec message.

bundler: command not found: rack

I've re-run bundle install / update a few time and each time that i try to boot my serve project it fails to start with the same error.

On the other hand, if I require the latest rack 1.3.4 and start a new project, i get the error but the serve server works. If i run the serve server on my existing project, the server boot but can't find the pages. it says something like:

/path/to/my/views/file.slim/path/to/my/views/file.slim

the path to the correct fil开发者_JAVA技巧e in my view folder get repeated twice and therefore doesn't load...