The API takes advantage of the server's opaque flag support and sets its
"complex" flag whenever the object being stored or retrieved isn't a plain
scalar. In that case, the Storable module is used to freeze and thaw the
value automatically going in and out of the memcached.

WWW: https://metacpan.org/release/Cache-Memcached
WWW: http://www.danga.com/memcached/