title: how to detect telephone numbers in a text (and replace them)?
body: <p>I know it can be done for bad words (checking an array of preset words) but how to detect telephone numbers in a long text?
  I'm building a website in PHP for a client who needs to avoid people using the description field to put their mobile phone numbers..(see craigslist etc..)</p>
  
  <p>beside he's going to need some moderation but i was wondering if there is a way to block at least the obvious like <code>nnn-nnn-nnnn</code>, not asking to block other weird way of writing like <code>HeiGHT*/four*/nine</code> etc...</p>