What about the standard sudo pecl install pecl-ev? Or maybe you're wondering how to upgrade PHP itself to 5.4?
Yes, phpize is always shipped with a "dev" package on all distros/OS'. I don't use OS X at all. But I've fixed a bug on it some time ago. It shouldn't be difficult to upgrade from ports. Compiling from source is always a good alternative.
Give me some extra info please. At a pinch, I can try to fix it via an SSH connection.
EDIT: Of course, the best way to install something is to use a package manager. So try to update the ports and just normally upgrade PHP and pecl-ev(don't know whether such an OS X port exists though). Let me know what issues are you experiencing(terminal output, error logs etc.)