Step 1 : Grab the latest version of libevent.

{syntaxhighlighter brush: bash;fontsize: 100; first-line: 1; }wget http://monkey.org/~provos/libevent-2.0.10-stable.tar.gz{/syntaxhighlighter}

The libevent API provides a mechanism to execute a callback
function when a specific event occurs on a file descriptor or after a
timeout has been reached. Furthermore, libevent also support
callbacks due to signals or regular timeouts

Step 2 : Extract and install libevent

{syntaxhighlighter brush: bash;fontsize: 100; first-line: 1; }tar xvzf libevent-2.0.10-stable.tar.gz
cd libevent-2.0.10-stable
autoreconf
./configure --prefix=/usr
make
sudo make install{/syntaxhighlighter}

Step 3 : Download and install Memcached

{syntaxhighlighter brush: bash;fontsize: 100; first-line: 1; }wget http://memcached.googlecode.com/files/memcached-1.4.5.tar.gz{/syntaxhighlighter}{syntaxhighlighter brush: bash;fontsize: 100; first-line: 1; }tar xvzf memcached-1.4.5.tar.gz
cd memcached-1.4.5
autoreconf
./configure --prefix=/usr
make
sudo make install{/syntaxhighlighter}

Restart apache and you should be good to go.