Session error

I installed a fresh copy of WP and installed the Newsletter plugin. Everything seemed to work fine, I worked on the site for another hour or so. However, today I go to the site and get the following error. I read a number of threads about this, but my PHP session path is /tmp and the directory does exist at /tmp on the server. This happened to me a couple weeks ago on a different site with the WHMCS plugin and I removed the plugin to solve it and haven’t tried installing it again. I need some advise on how to deal with this. This is a new cPanel VPS server and we are reselling hosting on it. We are new to WPMU plugins, though.

Warning: session_start() [function.session-start]: open(/tmp/sess_3f64b946cd2c0c7b772296be5fd3d9ae, O_RDWR) failed: Permission denied (13) in /home/casged/public_html/wp-content/plugins/e-newsletter/e-newsletter.php on line 1470

Warning: session_start() [function.session-start]: Cannot send session cache limiter – headers already sent (output started at /home/casged/public_html/wp-content/plugins/e-newsletter/e-newsletter.php:1470) in /home/casged/public_html/wp-content/plugins/e-newsletter/e-newsletter.php on line 1470

Warning: Cannot modify header information – headers already sent by (output started at /home/casged/public_html/wp-content/plugins/e-newsletter/e-newsletter.php:1470) in /home/casged/public_html/wp-includes/pluggable.php on line 866

Warning: Unknown: open(/tmp/sess_3f64b946cd2c0c7b772296be5fd3d9ae, O_RDWR) failed: Permission denied (13) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/tmp) in Unknown on line 0