Editing an event causes hour to be corrupted

Issue Summary

I running in a server with PHP 5.2.6-2ubuntu4.3 and apache (happened in others too but I have no details on them):
When editing an event time either for future or all events the hour of current event gets corrupted and after edition I end up at a future event (of the same sequence) view.
I checked the code and found that node was being corrupted because it was being copied by reference (I understand this is the default for php5) so I changed the copies for clones of the objects so it actually creates new objects.