wp_nav_menu after doesn't work.

I posted this in hacks and got no replies. It’s very frustrating and I need to know what to do next. wp_nav_menu doesn’t seem to work right. I am using the twentyten theme

I am trying to add a query string to the url of each menu element.

I found wp_nav_menu in the codex and tried

“link_after’ => ‘?q=something’ which added only to the link text and didn’t change the actual link.

Then I tried ‘after’ => ‘?q=something’ which sounded like it might work, but it didn’t seem to change anything.

Is there a way to do what I want? Is wp_nav_menu the right function?

To clarify, I want menu item links
href=”https://localhost/~wordpress/blogs/”
to become
href=”https://localhost/~wordpress/blogs/?q=something”