> I don't know if anyone on this list can give me a hand, but I'm trying to configure sendmail on our library's LAMP server. I have to use a different IP address specifically used for outgoing email instead of the box's IP. Does anyone know where/how I can configure this?
>

I don't know how to do this in sendmail since we configure our servers
to use postfix, but in postfix's main.cf, there's a variable called

smtp_bind_address = 111.222.333.444

that lets you specify the email origination IP. If your machine
doesn't really do much mailing, you might consider switching to
postfix since it's a lot easier to run and can be used as a drop in
replacement for sendmail and many of your favorite sendmail commands
work just fine with it.

If you need to add an IP to your NIC as well
http://www.cyberciti.biz/faq/linux-creating-or-adding-new-network-alias-to-a-network-card-nic/
may be of use to you assuming you're on linux.

kyle