When installing Memcached on a machine I came across the following error when I tried to start it:

memcached: error while loading shared libraries: libevent-2.0.so.5: cannot open shared object file: No such file or directory

The solution for this on Debian/Ubuntu (and probably most other linux distros) is this…

On a 32 bit system:

ln -s /usr/local/lib/libevent-2.0.so.5 /usr/lib/libevent-2.0.so.5

On a 64 bit system:

ln -s /usr/local/lib/libevent-2.0.so.5 /usr/lib64/libevent-2.0.so.5

After creating the appropriate symlink for your system you should now be able to start memcached as normal:

memcached -d -u memcached_user -m 256 127.0.0.1 -p 11211

Q.E.D.