How do I set up one email account with dual SMTP options?

[Chuck]

I use Outlook 2003 for my work email both at work and at home. At work I
connect via LAN, and at home and on travel via an ISP's dialup. I need to
give my work email account the option of sending email via the LAN, or via my
dialup's SMTP. Currently in Outlook 2003 I have set up 2 accounts, one for
work and one for my ISP's dialup. I have given the dialup account my work
userid and POP3 address, and the dialup's SMTP and specified a connection
through the dialup. That worked in Outlook 2000. But in 2003, whenever I
tap "send/receive", the dialup account tries to connect to my POP3 server
while I am connected to the LAN (vice the dialup connection), and I get
constant error messages.

What I need is a simple way, preferably without establishing two separate
accounts, to give my work email account the SMTP option of using my LAN
connection at work or my dialup connection at home. Failing that, I need to
understand how to prewvent my separate dialup account - which has my work
POP3 address - from trying to receive email when I am connected to the LAN.
It should be simple. Can anyone help?

v/r,
Chuck