Steps to reproduce:

1. Enter edit mode on Page A
2. On an alternate page, Page B, containing a Gliffy Diagram, select the Copy Diagram option
3. Add diagram to Existing Page and select Page A
4. Save

Expected result:

User editing Page A sees the Gliffy Diagram added to the editor and rendered properly

Actual result:

User editing Page A sees "Error 500" rendered instead

Other notes:

The user is still able to edit and update the page. Upon saving, the diagram gets rendered properly. When re-entering edit mode, the diagram is also rendered properly. If another user enters the edit session while the diagram is still displaying an error, the diagram updates to render properly.