Some more ideas:

• Start and End-Date of the Diagram should be editable independent fron Version start and end-Date
• Chart should be accesible as a Jira gadget, too
• Chart should be available for filters (cross-Project), too (in combination with possibitlity to set the start and end-Date of the chart displayed

Some questions:

• Does it also work for custom issue-status definitions (we have new, assigned, waiting for clarification, in progress, resolved, verified in our process.