title: NS_ERROR_MALFORMED_URI in FF when calling document.location.replace()
body: <p>I'm seeing the following exception in FF 3.5.6:</p>
  
  <pre><code>uncaught exception: [Exception... "The URI is malformed"  nsresult: "0x804b000a (NS_ERROR_MALFORMED_URI)"  location: "JS frame :: http://x :: refreshPage :: line 193"  data: no]
  </code></pre>
  
  <p>This error occurs when calling document.location.replace("/relative/url") on the parent window of an iframe.</p>
  
  <p>It's also reproducible in FF2, but IE8 doesn't exhibit the problem.</p>
  
  <p>EDIT: The following code in the same context doesn't have the problem:</p>
  
  <pre><code>document.location.reload();
  </code></pre>