I want to send email from mydomain.com but have them all bounce to
xyz.com. The problem is when I use the -f option with mail , I get my
emails all rejected by xyz.com, saying that 'Sender domain is
spoofed'. I looked at the headers and it appears adding -f sets the
'envelop-from' header which causes xyz.com to think it is spoofed. I
tried using 'Errors-To' header but that did not work and appears to
be deprecated anyways. I also tried using the -f and just relying on
the 'Reply-To', but that did not send bounced emails to 'Reply-To'
xyz.com address.

I want to send email from mydomain.com but have them all bounce to

xyz.com. The problem is when I use the -f option with mail , I get my
emails all rejected by xyz.com, saying that 'Sender domain is
spoofed'. I looked at the headers and it appears adding -f sets the
'envelop-from' header which causes xyz.com to think it is spoofed. I
tried using 'Errors-To' header but that did not work and appears to
be deprecated anyways. I also tried using the -f and just relying on
the 'Reply-To', but that did not send bounced emails to 'Reply-To'
xyz.com address.
>

In http://www.faqs.org/rfcs/rfc2822.html , there is some info on
resent-headers. They are used to redirect a message after you have
received it yourself (like a message sent to "info@example.com" and then
redirected to the person that can best answer it).

Best regards