If I use:
Qt Code: 
  1. HTML = u"<html><body>++\U00012000++</body></html>"
  2. qStr = QString(HTML)
  3. print qStr.toUtf8()
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then the HTML string with the correct glyph in it is printed.

If I use:
Qt Code: 
  1. #!/usr/bin/env python
  2. # -*- coding: UTF-8 -*-
  3. '''
  4. Created on 7 November 2012
  5.  
  6. @author: nick
  7. '''
  8.  
  9. import sys
  10.  
  11. from PyQt4.QtCore import QString
  12. from PyQt4.QtGui import QApplication, QWidget
  13. from PyQt4.QtWebKit import QWebView
  14.  
  15. # Constants
  16. CUNE_STR = u"\U00012000"
  17. HTML = u"<html><body>++%1++</body></html>"
  18.  
  19. # Main
  20.  
  21. qStr = QString(HTML).arg(QString(CUNE_STR))
  22.  
  23. app = QApplication(sys.argv)
  24.  
  25. widget = QWidget()
  26.  
  27. widget.resize(320, 240)
  28. widget.setWindowTitle("Hello, World!")
  29. widget.show()
  30.  
  31. webView = QWebView(widget);
  32. webView.setHtml(qStr);
  33. webView.show()
  34.  
  35. sys.exit(app.exec_())
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then the same problem occurs: a window pops up with: ++<two empty boxes>++.