SMS query: can you add an unknown contact number direct from text ?

Hi,

Just been doing this on my SE W550, so wonder if it's possible with the iPhone.

When receiving a text from an unknown source (say a friend who has changed their number so it doesn't come up with their name initially), can you add the number to your list of contacts from the SMS options or do you have to manually note the number down and go to Contacts etc ??