Saving dependent objects in a has_many relationship

Hello everybody,

Quick question. Let's say I have two models: Trouble_Ticket and
Issues. Trouble_Ticket has_many Issues and Issue belongs_to
Trouble_Ticket -- a classic has_many.

When I do Trouble_Ticket << Issue, Issue is automatically inserted
into the db. But if I do this:

x = Trouble_Ticket.find :first
x.issues {|issue| issue.status_id = 2 }

... and then

x.save

... the issues are not automatically updated. Why?

I couldn't find an answer to this anywhere.

Thanks for any clues.