What distro are you running? It's possible that there is no more recent version of cmake in its repositories. In that case, you'll have to either upgrade your distro, see if you can find a backported package, or build the later version of cmake from scratch yourself.
BTW, in my experience cmake is a horrid PITA to get working correctly, especially when you need to change paths to dependent header files and libraries. Its use should be strongly discouraged, IMO (of course if you have a piece of software that expects to use it, then you don't have much choice).