If you right click a file in Nautilus and select Compress, then you get a dialog where you can choose a compression format and a filename. If you click on Advanced, then there are settings to split and compress the file, but it's deactivated/insensitive. How come and how do I activate those features?

Edit: In an answer below, it has been suggested that it has something to do with rar. But I have that installed, and I don't get the options to split.