title: iPhone: UIView with 1 pixel height
body: <p>I'm trying to create a <code>UIView</code> with 1 pixel height.</p>
  
  <pre><code>     UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0,0,20,1)];
  </code></pre>
  
  <p>On a non-Retina iPhone it's ok, but on Retina it looks like 2 pixels height.</p>
  
  <p>What's wrong ?</p>