This article will show how we can install updated versions for memcached (and libevent) for Debian Etch, by backporting the packages from debian testing.
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Why would we want to do this? Because the versions shipped with Etch are old, and accordingly to the software creators should not be used as the new versions provide much better performance and reliability:
libevent: version in etch: 1.1a (released on 2005-06-12).
memcached: version in etch: 1.1.12 (released on 2005-04-04)