Update inc/plugins/sceditor.php

$jquery = '<script src="jscripts/sceditor/j
query-1.8.2.min.js?ver='.SCEDITOR_PLUGIN_VER.'"></script>';

to:

$jquery = '<script src="jscripts/sceditor/jquery-1.8.2.min.js?ver='.SCEDITOR_PLUGIN_VER.'"></script>';