I'm seeing "Runtime environment: Unknown" in my agent log files even though I'm running a supported environment

This error will appear in newrelic_agent.log files that are generated by rake tasks, scripts and other jobs outside of the application server. The agent doesn't generally get activated for these tasks.

These log files are distinguished from those generated by the agent running in your mongrel, thing, etc., instance by the fact that they don't include an agent identifier, such as '3000' in the log file name; i.e., newrelic_agent.3000.log, newrelic_agent.3001.log, etc.