Client writes a bug report: This and that doesn't work.
Me: This functionality never was implemented. Please open a feature request.
Client: But this is a bug. Without this feature, the service won't work as we expect.
Me: But this wasn't in the requirements for release. So you have to contact the PM for a feature request.
Client: THIS IS A BUG! FIX IT!
Me: GO FUCK YOURSELF! THIS IS A NEW FEATURE AND YOU HAVE TO PAY FOR IT!
Unfortunately, I never sent the mail. But I kept it in the drafts. Maybe someday...