When you don't have a comment form in a page/post/index this plugin tries to insert it anyways and it results in a javascript error (in IE) so the solution I found was to open openid/interface.php and modify the following function as show. in my case I only want comments on single posts, not the index or pages (no comment forms there).
function comment_form() {
if (!is_user_logged_in() && is_single() && !is_page()) {
echo '<script type="text/javascript">add_openid_to_comment_form()</script>';
}
}
Hope this helps other people