title: iOS 5.1 : -[UIColor colorWithPatternImage:] background color draws solid black
body: <p>While testing my application in today's release of iOS 5.1 GM, I noticed that some of my views are drawing solid black rather than their patterned background color.  The exact same code works fine on previous iOS releases (tested on 4.2 - 5.0.1).</p>
  
  <p>See screenshots:
  <img src="https://i.stack.imgur.com/J302g.png" alt="Screenshots of issue"></p>
  
  <p>Has anybody else experienced this?  Is there a workaround?</p>