Hi, I'm not sure if this is the best place to ask this, but here goes:
I was wondering how to do this: I want to have Exim (the mail server) open on port 80 on my server (say, myserver.com), however I also have a website that needs to be visible (on port 80), at least on www.myserver.com and also myserver.com if possible.
I need Exim open on port 80 because many of my users are accessing Exim from networks where port 80 is the only port that is open (e.g. airports).
What would be the best way to do this? I don't want to have to have port80.myserver.com as the server.
Having two different processes listening both to port 80 on the same IP address on a server is not possible, but you can request your host for a second IP address and configure exim to listen to port 80 requests on that IP. You probably have to reconfigure your webserver for this, because default at least Apache listens on all IP's available.
Another idea might be to use port 443 for exim, if you don't serve SSL content via your server. Port 443 is normally used for https:// type requests and is probably also opened at airport networks.