How to make www.x.com and x.com the same, one should be redirect 301?
Not really a Drupal question, but I'll still have a go.
I believe this is the sort of thing CNAME (Canonical Name) is designed to do: http://en.wikipedia.org/wiki/CNAME_record
You configure this in your DNS setup.
Your A record is supposedly x.com, and then create a CNAME record giving it the alias www.x.com.
(I would not use Apache redirect for this.)
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