Upgrade to WordPress 2.9.2
Upgrading to Wordpress 2.9.2 will close the security hole where contributors can see posts in your trashcan even if they were sensitive or created by the admin.
wordpress trashcan
WordPress 2.9 Features and Functionality Improvements
Keith Dsouza from Weblog Tools Collection did an excellent write up showing off the new features of Wordpress 2.9 beta 2