See the ILUG archives for this one.
The short version is thatyou can but it's a hack - see the sendmail FAQ for how to do this.
As others have pointed out, doing such a thing messes with the RFC standards, and totally fscks any encryption/ digital signatures. To avoid this, the sig should be inserted by the client and not the MTA.
Digital TV Technologies,
SMS messaging - http://gmccloskey.virtualave.net
#From: ilug-admin at linux.ie [mailto:ilug-admin at linux.ie]On Behalf Of Paul
#Sent: Wednesday, November 22, 2000 10:25 AM
#To: ilug at linux.ie
#Subject: [ILUG] appending signature in sendmail
#Anyone know how I can add a company signature to all outgoing mails by
#configuring Sendmail? Using this, clients wouldn't even have to be aware
#that there was company info being appended to their emails. I've
#how to do it from client side (no problem there - see wise old jedi test
#signature below) but I'm sure Sendmail allows this feature somehow. Anyone?
#"Do or do not.......there is no try" - old Jedi saying
#Irish Linux Users' Group: ilug at linux.ie
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