Could not find rake-10.3.2 in any of the sources

I installed gitlab using this instructions: https://gitlab.com/gitlab-org/gitlab-ce/blob/7-4-stable/doc/install/installation.md

Now, almoust everything worked fine, but when I tried to push something to the server, I get errors, amongst others:

[...]
Counting objects: 3, done.
Writing objects: 100% (3/3), 252 bytes | 0 bytes/s, done.
Total 3 (delta 0), reused 0 (delta 0)
remote: /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/spec_set.rb:92:in `block in materialize': Could not find rake-10.3.2 in any of the sources (Bundler::GemNotFound)
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/spec_set.rb:85:in `map!'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/spec_set.rb:85:in `materialize'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/definition.rb:132:in `specs'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/definition.rb:177:in `specs_for'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/definition.rb:166:in `requested_specs'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/environment.rb:18:in `requested_specs'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/runtime.rb:13:in `setup'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler.rb:121:in `setup'
remote:         from /usr/local/lib/ruby/gems/2.1.0/gems/bundler-1.7.4/lib/bundler/setup.rb:17:in `<top (required)>'
remote:         from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
remote:         from /usr/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
To https://[servername]/[username]/helloworld.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://[servername]/[username]/helloworld.git'

And now I really don't know what to do.