add option to url

I use the link module to make links to youtube videoes. It is simpler and better than emfield. And I like the integration to lightbox2. But I can't find how to add a "?autoplay=1" and other things to the end of the url. I can add it to every link, but I want to make it in the field configuration like the "rel=" option. To make it in the field display menu looks a bit too complicated (a lot of php-programming).
Maybe it is a feature reqest?