Protect against cold boot attacks?

"Fred ." <[email protected]> Thu, 24 Nov 2011 00:20:32 +0100
Newsgroups org.kernel.vger.linux-admin
Message-ID <CAJgfmqXArW9JmgaJ+Z=tDVgu8ZscKLFS_6AWUjh15eg2rVa48Q@mail.gmail.com>
Will
su-c 'sync; echo 3 > /proc/sys/vm/drop_caches'
protect against cold boot attacks?

Is there anything that will protect against cold boot attacks?