Right have a look at the screenshot below.
I started writing an SMS, accidentally hit some shortcut thing (I do it all the time) and my draft is saved into the conversation, as you can see.
Then I can start a fresh draft, with the old draft put to one side in the thread.
http://img14.imageshack.us/img14/766...0571719274.jpg Image blurred to protect privacy
I'm determined to find out how to do this because I keep doing it by accident and it would actually be a really handy feature if I could use it properly!