If you don't want to wait for 1.4 or do it with svn, you could also implement a semi-functional multiline text display using an IGUIListBox in 1.3. However, in 1.3 it doesn't have a horizontal scroll, so you'd either have to add that yourself or break the lines yourself.
By the way bitplane, will list boxes have autoscroll and horizontal scrollbars in the new version?