I see some error when starting a rake task on Heroku

```
ERROR : Unhandled error in worker thread, disconnecting this agent process:
** [NewRelic][03/13/14 08:11:24 +0000 ce386287-971c-443c-8031-21ea3a6ce24a (2)] ERROR : NoMethodError: undefined method `sendReport' for nil:NilClass
** [NewRelic][03/13/14 08:11:24 +0000 ce386287-971c-443c-8031-21ea3a6ce24a (2)] ERROR : Debugging backtrace:
/app/vendor/bundle/ruby/2.0.0/gems/oboe-heroku-0.9.9.0/lib/heroku_metal.rb:63:in `sendReport'
  /app/vendor/bundle/ruby/2.0.0/gems/oboe-2.6.1.0/lib/oboe/api/logging.rb:125:in `log_event'
  /app/vendor/bundle/ruby/2.0.0/gems/oboe-2.6.1.0/lib/oboe/api/logging.rb:90:in `log_entry'
  /app/vendor/bundle/ruby/2.0.0/gems/oboe-2.6.1.0/lib/oboe/api/tracing.rb:34:in `trace'
  /app/vendor/bundle/ruby/2.0.0/gems/oboe-2.6.1.0/lib/oboe/inst/http.rb:17:in `request_with_oboe'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/instrumentation/net.rb:27:in `block (2 levels) in request_with_newrelic_trace'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent.rb:403:in `disable_all_tracing'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/instrumentation/net.rb:26:in `block in request_with_newrelic_trace'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/cross_app_tracing.rb:37:in `trace_http_request'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/instrumentation/net.rb:23:in `request_with_newrelic_trace'
  /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/net/http.rb:1369:in `block in request'
  /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/net/http.rb:852:in `start'
  /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/net/http.rb:1367:in `request'
  /app/vendor/bundle/ruby/2.0.0/gems/rest-client-1.6.7/lib/restclient/net_http_ext.rb:51:in `request'
  /app/vendor/bundle/ruby/2.0.0/gems/oboe-2.6.1.0/lib/oboe/inst/http.rb:11:in `request_with_oboe'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/new_relic_service.rb:360:in `block in send_request'
  /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/timeout.rb:66:in `timeout'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/new_relic_service.rb:358:in `send_request'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/new_relic_service.rb:298:in `invoke_remote'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/new_relic_service.rb:70:in `get_redirect_host'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/new_relic_service.rb:61:in `connect'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:782:in `connect_to_server'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:793:in `query_server_for_configuration'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:889:in `connect'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:649:in `block (2 levels) in deferred_work!'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent.rb:403:in `disable_all_tracing'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:644:in `block in deferred_work!'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:624:in `catch_errors'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:643:in `deferred_work!'
  /app/vendor/bundle/ruby/2.0.0/gems/newrelic_rpm-3.7.3.204/lib/new_relic/agent/agent.rb:676:in `block in start_worker_thread'
```