I'm playing this game as the Persians with C3C on deity, and after a short war with the Babylonians I got a military Great Leader, which I sent back to my capital to use on an important wonder later on, like you do. After the war I made a beeline straight for literature so I could get the great library. Anway, the strange thing is that although I can tell a city to build the Great Library, I can't hurry it with my leader. I can hurry other buildings, such as a library or a granary but as soon as I set the city to build the GL, the hurry-with-leader icon disappears and I can only build an army! Any idea why this is? I've never encountered anything like this before.