Following snippet will disable it for post_type post
(modify array below to affect other post_types):
function qtrans_disable()
{
global $typenow, $pagenow;
if (in_array($typenow, array('post')) && // post_types where qTranslate should be disabled
in_array($pagenow, array('post-new.php', 'post.php')))
{
remove_action('admin_head', 'qtrans_adminHeader');
remove_filter('admin_footer', 'qtrans_modifyExcerpt');
remove_filter('the_editor', 'qtrans_modifyRichEditor');
}
}
add_action('current_screen', 'qtrans_disable');
Similarly you can disable it for specific post IDs. However take into account that this won’t affect already existing multi-languaged content. Therefore use it before you enter any.