I'm new to theming and I am trying to use a zentropy subtheme with CiviCRM on Drupal 7. When I make the new subtheme the default, and click on CiviCRM in the menu, the CiviCRM menu does not replace the Drupal menu as it does with other themes. Is there a simple fix for this? If not, where can I start to look for the solution?

thanks!