title: Installing Qt on Linux (Debian distribution)
body: <p>I have Qt  4.6.3 on Debian. I need version 4.8.1. </p>
  
  <p>To install it I downloaded the <strong>Qt SDK 1.2.1</strong> from the Qt site, where is said that it contains version 4.8.1
  After installation I checked Qt version and it is 4.6.3 instead of expected 4.8.1.</p>
  
  <p>What I am doing wrong? And how can I install 4.8.1?</p>