Can't create new Iterations

Hi,

I want to create new Iterations but I can't save them on the server because the development line is immutable. How can I add a new Iteration?

I used the following code:

...
IDevelopmentLine devLine = service.getDevelopmentLine(teamArea, null);

IIteration i = s.createIteration();
i.setName("My Iteration has no name");
i.setDevelopmentLine(devLine);
i.setId("M5");

s.save(i, null);


Thanks in advance,
Kai