$ cd libevent-version
$ /usr/local/php/bin/phpize
$ ./configure --with-php-config=/usr/local/php/bin/php-config

error: Cannot find libevent headers

wget http://cloud.github.com/downloads/libevent/libevent/libevent-2.0.20-stable.tar.gz
tar zxvf libevent-2.0.20-stable.tar.gz
cd libevent-2.0.20-stable/
./configure --prefix=/usr/local/libevent-2.0.20-stable/
make
make install
cd ../

$ cd libevent-0.0.5
$ /usr/local/php/bin/phpize
$ ./configure --with-php-config=/usr/local/php/bin/php-config --with-libevent=/usr/local/libevent-2.0.20-stable
$ make && make install