Url Ridirects Question

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I wonder is it possible if someone posted a link lets say www.amazon.com can i make it so that it redirected to www.wallmart.com

Thanks

[SEOvB]

AdminCP -> Styles and Templates -> Replacement Variables

But it will change all the www.amazon.com links, and not just the ones currently posted

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But how would I make it so it wouldnt appear in the title though?