Missing topic when creating thread after having an error for repeating name/url

[numeroteca]

1. Create a thread with 1 topic with the same name as an existing thread.
2. It detects the error and asks the user for a new thread name.
3. The topic created in step 1 is lost and now appears topic number 2.
4. Create thread.

When displaying gives an error and the user is not able to edit the topics to solve it.

Example at http://production.pageonex.com/threads/movilizaciones-mayo-2013-b

The problem seems to be related to the topic update and creation.