Need help with SMTP virtual servers IP in IIS 6.0

[Guest lca1630]

I have having an issue with the title of this post. I have multiple IP

addresses configured on my server, and when I go to create my smtp virtual

server, it doesn't allow me to configure any of these IP's, only the loopback

and unassigned all. I have tried editing and adding in the general tab

advanced menu, but nothing. I must be missing something taht would enable

these addresses to be used for this. Pleas help. Thanks - Nik