[str_replace] Problem in vb4

[omardealo]

Hello every one ,

i used that code but not worked

Hook : parse_templates

code :

PHP Code:

$ain_nocopy = '<SCRIPT LANGUAGE="JavaScript"> CODE </SCRIPT>';

$ain_nocopy_css = '<style type="text/css">.ain_unselectable{CODE}</style>';

$search_text = '<!-- / CSS Stylesheet -->';

$vbulletin->templatecache['headinclude'] = str_replace($search_text, $ain_nocopy_css.$search_text.$ain_nocopy , $vbulletin->templatecache['headinclude']); 


i know that "<!-- / CSS Stylesheet -->" not found in template headinclude , but i add it and still code not worked
Where the problem, thank you