UNIX for Dummies Questions & Answers

Hi,
I use mailx to send short notifications to a bunch of users ( in Lotus Notes ). The undeliverable emails are going to the Notes' Dead Letter basket and creating a problem. I am told by the Notes Admin that I need to specify a 'Return address' so that the bounced emails can go there. I can not find any flags/information as to how to tell MAILX to use a different email address as the "return/dead" address. Is there such a thing ?
OR is this a Lotus Notes problem in that it is not sending them all back to the originating UNIX email account ?

Can you not prefix you message with the SMTP headers?

eg

Reply-To: <address>

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