TeamCity runner fails, though manually I can make it work

I have installed TeamCity and have run into a problem.  Basically what I've done is to create a simple scenario.  I forked one of Wolfram Arnold's teaching apps to my own repository, then manually did the following:

$ git clone git@github.com:purplejacket/Efficient-Test-Driven-Rails-Development.git
$ cd Efficient-Test-Driven-Rails-Development
$ rake db:migrate
$ rake spec

93 examples, 0 failures

However, when I try to set this up to run through TeamCity, I get the following:

Build errors

[14:03:11]: Execute spec (2s)
[14:03:13]: [Execute spec]
RuntimeError: Command /home/kai/.rvm/rubies/ruby-1.8.7-p302/bin/ruby -I"lib"  "/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rspec-1.3.0/bin/spec" "spec/controllers/people_controller_spec.rb" "spec/models/order_spec.rb" "spec/models/customer_spec.rb" "spec/models/message_spec.rb" "spec/models/order_item_spec.rb" "spec/models/user_spec.rb" "spec/models/address_spec.rb" "spec/models/item_spec.rb" "spec/models/person_spec.rb" "spec/lib/mock_spec.rb" "spec/lib/array_commutation_spec.rb" "spec/routing/people_controller_routing_spec.rb" "spec/views/people/_person_form.html.erb_spec.rb" --require 'teamcity/spec/runner/formatter/teamcity/formatter' --format Spec::Runner::Formatter::TeamcityFormatter:matrix failed


Stacktrace:
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rspec-1.3.0/lib/spec/rake/spectask.rb:177:in `define'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:1112:in `verbose'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rspec-1.3.0/lib/spec/rake/spectask.rb:153:in `define'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:636:in `call'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:636:in `standard_execute'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:631:in `each'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:631:in `standard_execute'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:260:in `execute'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:90:in `target_exception_handling'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:266:in `execute'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:597:in `invoke_with_call_chain'
/home/kai/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/monitor.rb:242:in `synchronize'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:583:in `standard_invoke_with_call_chain'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:235:in `invoke'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:90:in `target_exception_handling'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:234:in `invoke'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2029:in `each'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:311:in `standard_exception_handling'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:2001:in `run'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:311:in `standard_exception_handling'
/home/kai/.rvm/gems/ruby-1.8.7-p302/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rake_ext.rb:179:in `run'
/home/kai/TeamCity/buildAgent/plugins/rake-runner/lib/rb/runner/rakerunner.rb:40
[14:03:13]:
Rake aborted!

$ rake db:migrate
$ rake spec
93 examples, 0 failures