Off Topic - Exim question

[Jayson Smith]

The reason I'm marking this as off topic is that it isn't related to
Speakup.
Anyway, I'm trying to use my local Linux box as an SMTP server for my lan.
I've enabled relaying for 192.168.0.0/8 which covers my entire lan.  But
certain Internet servers think that, since I'm on a residential DSL line, my
SMTP server can only mean one thing...  Spam!  Some will even disconnect me
right on the spot.  So my question is, what steps do I need to take with
Exim 3.35 I think it is, whatever comes with Debian Woody Stable, to make it
use my ISP's SMTP server to send outgoing mail?  The reason I want to use my
local server to start the process is that sometimes Outlook Express takes a
long time sending certain messages, and it doesn't when it's configured to
use my local server.  Any thoughts?
Thanks in advance,
Jayson.