IMAP email on laptop questions

ive got a few questions that i really need answered before i use my IMAP on my laptop.

the incoming server is always the same, no matter what my location is, i understand that part.

however here is what i am confused on. Since its a laptop, the outgoing server changes depending on where the laptop is correct? since i have comcast at my house, my outgoing server is smtp.comcast.net
when im at school there server is tiger.towson.edu

and when im elsewhere, say at a coffee house or something, how can i send emails?

can i config the mail app in OSX for various IMAP outgoing servers, and how will it know which one to use thatll work?

Most of the time, you can use a single SMTP server wherever you are, regardless of which network connection you're using. I use the same server from home, work, Panera, my parents' house....

The only time you might have a problem is if your ISP blocks access to port 25 (which is the normal port for SMTP.) Many ISPs do this to prevent spam, and only allow access to their own particular mail server.

In my case, I have a .mac account and use smtp.mac.com as my outgoing mail server. Because my ISP blocks port 25, I have to use SMTP on port 587, which the .mac SMTP server supports for exactly this reason.

Usually, though, you can find one server that will work from anywhere.

ive been reading a bit... its seems as though if i switch wifi networks from one to another, OSX WILL REVert to the server that mail was set to last time i was on that network.

while this is a good idea, i think i had trouble with this part in the past.

You can set up mulitple outgoing mail servers. If one fails on send, mail.app will prompt you to choose another from the dropdown list (or add another). It's not a big deal.