Remove CDATA script from the page source
I'm assuming you're using an HTML5 DOCTYPE, The CDATA tags are required for XML-based documents (including XHTML).

The characters look to be hard-coded into common.inc, line 4287:

$embed_prefix = "\n&lt;!--//--&gt;&lt;![CDATA[//&gt;&lt;!--\n";
$embed_suffix = "\n//--&gt;&lt;!]]&gt;\n";


Examining that code I think the only way to intercept it would be to override theme_html_tag() in your theme, e.g.

function MYTHEME_html_tag($vars) {
  if ($vars['element']['#tag'] == 'script') {
    unset($vars['element']['#value_prefix'];
    unset($vars['element']['#value_suffix'];
  }

  return theme_html_tag($vars);
}