How do I change the envelope from address in sendmail

[BALU G.S]

   Hi,

   What's the proper way to
   get sendmail to use [1]user at domain.com instead of [2]user at
   machine.domain.com?????

   Regards,

   Balu
     _________________________________________________________________

   Drive away out of trouble. [3]Get a loan against your existing car.

References

   1. http://lists.freebsd.org/mailman/listinfo/freebsd-questions
   2. http://lists.freebsd.org/mailman/listinfo/freebsd-questions
   3. http://g.msn.com/8HMBENIN/2746??PS=47575