I have a server running python, php, perl, ruby, and I have couple applications which also send mail. I was wondering in case if one of the applications don't specify a from email address, the sender email address is set to http@example.com and the sender name was "http". 
I was able change the sender name by going into /etc/passwd and changing the name to what I wanted, but how do I change http@example.com to admin@example.com?
 
     
    