title: UIColor `-colorWithPatternImage:` alpha blending problem solution. (iOS SDK 4.1)
body: <h1>Solution note, not a question.</h1>
  <p>I used this code to set background as a pattern image:</p>
  <pre><code>UIImage *bg     =   SomeImage();
  UIColor *bgc    =   [UIColor colorWithPatternImage:bg];
  [self setBackgroundColor:bgc];
  [self setOpaque:NO];
  </code></pre>
  <p>This works, but alpha blending doesn't work. Might be a bug. How to make it work?</p>
  <ul>
  <li>Platform: <code>iOS SDK 4.1</code></li>
  </ul>