Steps to Reproduce:
Create a new diagram.
Save it, filling in all three boxes.
Save it again. Note that the first box still has the old name and is greyed out
The second save should result in a save failed. Attempting to perform a "Save as" with similar steps results in the same issue.
Save the diagram once, then close and reopen it.
Ubuntu, Tomcat 6.0.29, Ant 1.7.1