Submitting "Follow up" issue displays "Page not found"

We had this problem in 4.4 and we have it again in cvs. When we submit a follow-up to an issue, we get a Page Not Found error because the page redirected to has an extra ?q=

We have clean URL's *disabled*, and the URL of the redirected page is, for example: mydomain.com/?q=?q=node/110