Did you know that Pentaho Data Integration includes Experimental Transformation steps? Experimental steps encourage proactive testing and critical feedback from the user community. The reported results are used to harden the product for the next revision. You can always provide your feedback, suggest new features and report issues here on our tracking site for any of Pentaho's product offerings.
One of the experimental steps available in PDI version 4.1 is the ETL Metadata Injection step. This Transformation step is used to dynamically set another transformation's step metadata, i.e the actual editable properties of a step.
Transformation steps already ........ read more of this topic and download a working sample here at the Pentaho Evaluation Sandbox.