from header, how to control whats in the parens ()

I am sending mail via postfix, when I receive the mail, the from
header looks like this:

From: andrew@somewhere.com (me)

I really want the (me) to be (andrew). It is picking up the (me) from
the currently logged in user on the ubuntu system, which is
username=me.

my main.cf contains this line:
smtp_generic_maps = hash:/etc/postfix/generic

and my /etc/postfix/generic contains these lines:
me@ubuntu.localdomain andrew@somewhere.com
@ubuntu.localdomain andrew@somewhere.com


Any ideas how get the (me) to be (andrew). Must be a config line
somewhere !!!