How frequently does the letter i appear in:
Q: How do I configure the default email sender properties on a debian server? How can I configure the default mail sender properties on a debian server (with a mail transport agent of exim4, if it matters)?
Background
Im running a server (debian 5, the mta is exim4) hosted by rackspace.  Rackspace mail uses outgoing sender address authentication, such that I can only send email from vetted from addresses.
Sending as, say, a local user results in a rejection:
  SMTP<< 550 5.1.0 <localuser@domainname.com>: 
Sender address rejected: User unknown in relay recipient table
  SMTP<< 554 5.5.1 Error: no valid recipients
  SMTP>> QUIT
LOG: MAIN
  ** webadmin@domainname.com R=smarthost T=remote_smtp_smarthost: 
SMTP error from remote mail server after RCPT TO:<webadmin@domainname.com>:
 host smtp.emailsrvr.com [xxxxxxx]: 550 5.1.0 <localuser@domainname.com>: 
Sender address rejected: User unknown in relay recipient table

Problem is, Im using a really simple app (logcheck, http://packages.debian.org/unstable/logcheck ) in an attempt to simply email out logs to myself. Logcheck doesnt have any built-in configuration for where the mail get sent from.
So whatever is the default is getting set as, by the system, I need to configure it to make sure its a vetted address.  Where do I start?

A: Theres a /etc/email-addresses that associates outgoing email addresses with local user accounts (its part of the default rewrite config of Debians Exim). I think this is the better solution for your problem. 
Also, during a dpkg-reconfigure exim4-config theres an option Hide local mail name in outgoing name, see if it can help you.

user
I counted 95 "i"s in that text.
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