title: How do I compile Qt Designer 4.0 XML files with Qt uic version 4.2.1?
body: <p>I have searched long and hard on Google, and found much information regarding the use of uic3 to convert Qt3.3 XML to Qt4 for compilation, but nothing on what to change or look for in .ui files generated with Qt4 (4.0) that fail to compile.  Here's a sample of my output from trying to run uic on each .ui file (I'm compiling the latest edition of Firewall Builder, for reference) As you can see, several of the files fail and one here, 'asklibforcopydialog_q.ui' succeeds</p>
  
  <pre><code>[atroon@alexandria libgui]$ ls *.ui | xargs -n1 uic |more
  uic: File generated with too old version of Qt Designer
  File 'aboutdialog_q.ui' is not valid
  uic: File generated with too old version of Qt Designer
  File 'actionsdialog_q.ui' is not valid
  uic: File generated with too old version of Qt Designer
  File 'addressrangedialog_q.ui' is not valid
  uic: File generated with too old version of Qt Designer
  File 'addresstabledialog_q.ui' is not valid
  /********************************************************************************
  ** Form generated from reading ui file 'asklibforcopydialog_q.ui'
  **
  ** Created: Tue Dec 20 10:03:26 2011
  **      by: Qt User Interface Compiler version 4.2.1
  **
  ** WARNING! All changes made in this file will be lost when recompiling ui file!
  ********************************************************************************/
  (many more lines snipped)
  </code></pre>
  
  <p>So.  Do I need to try to find an old version of <code>uic</code>?  <strong>Or is there a relatively straightforward (regex, sed/awk) change that  I can make to the XML to allow it to compile with this version?</strong>  I can't imagine making a compiler not backward compatible within the same major version, but here we are.  Preliminary examination of the XML files that work like the one above that does compile and the ones which throw the <code>uic: File generated with too old version of Qt Designer</code> error does not reveal an obvious difference in the XML, but  an XML guru I am not.  </p>
  
  <p>Help me Stack Overflow, you're my only hope!</p>