:not() selector not working on IE (6 to 9)

:not() selector not working on IE (6 to 9)

Hello everyone,

Here is my problem : I want to select all the h2 in my #corps container, except those with a .post-title class.
The following selector doesn't work with IE (from 6 to 9). No problem with Chrome, Firefox, Opera.
  1. #corps h2:not(#corps h2.post-title)
The HTML:
  1. <div id="corps">
  2. <div id="contenu">
  3. <h2>Actualités</h2>
  4. <div class="post">
  5. <div class="post-head">
  6. <div class="post-avatar"><img alt="img" src="/img.jpg" /></div>
  7. <div class="post-title-info" >
  8. <h2 class="post-title"><a href="/blah">Blah</a></h2>
  9. <p class="post-info right">
  10. Blah Blah
  11. </p>
  12. </div>
  13. </div>
  14. <div class="post-content">
  15. <p>Blah blah blah.</p>
  16. </div>
  17. </div>
How could I fix this?

Thank you for your help !