If a dev wants to take this on, you need to modify two files.
SW
FontHelper.java
ENGINE
FlxBitmapFont.as
The goal is to modify the SW font writing routine to stop writing at 2880 and wrap back around and start a new line. You must modify the code that stores the horizontal offsets, so that it now stores both vertical offsets and horizontal offsets.
Then, you need to modify the engine code to stop assuming you only get horizontal offsets and take vertical ones into account.
Don't worry about the edge-case where both the horiz and vert dimensions as 2880.