Activation Error: Warning: main(WP_PLUGIN_DIR/contact-form-7/settings.php)

Hi,
I get a fatal error message when activating.

Warning: main(WP_PLUGIN_DIR/contact-form-7/settings.php) [function.main]: failed to open stream: No such file or directory in /home/u5/karlruegg/wordpress/html/wp-content/plugins/contact-form-7/wp-contact-form-7.php on line 67

Any ideas?
Karl

http://wordpress.org/extend/plugins/contact-form-7/