title: Can't change defaultValue attribute of input using jQuery
body: <p>I have some onfocus/onblur handlers for a field that clears the default contents when focused, but only if the value equals the default value (so as to not remove any user input).</p>
  
  <p>The field can also toggle between inputs. So rather than accepting a username, the user could click a button and it would accept an email address. This would require a different default value, such as "enter your email address". The actual property attribute <code>defaultValue</code> needs to be changed to allow my focus/blur handlers to work properly, using something like this:</p>
  
  <pre><code>$('input#ident-field').prop('defaultValue', 'enter your email address');
  </code></pre>
  
  <p>This doesn't seem to work because if you focus the field when it asks for an email address it doesn't clear it.</p>