I have a similar issue. Over the holiday we installed a new copy of Windows 2003 and put Exchange 2003 on it. seems to run fine the server is the DC and the server also host the web site. My DC is company.local and this seems to be fine but I missed something in exchange because it allows me to send from the local client to an out side recipiant but the mail address shows up as "user@company.local" rather than "user@company.com". This is a useless reply address, but here is the kicker, I can send an email to "user@company.com " and it will get there.
Can anyone help me figure out what I missed? Thanks in advance.
James