Error message: Fatal error: Call to undefined function jexit() in /home/mysite/public_html/plugins/content/cd_ajaxvote/utils/php/ajax.php on line 131

Solution: The jexit() function was added in Joomla! 1.5.3
Check your Joomla! version and if this is the case, first of all UPGRADE your Joomla! installation.

However you can open the ajax.php file located in /plugins/content/cd_ajaxvote/utils/php directory and replace all "jexit" strings with "exit" (without "j").