*grins* First off - welcome aboard! You're starting the journey into a wonderful land.

The first thing I'd do is read Learning Perl (if you're new to programming) and Programming Perl. Read them through. They will be the most invaluable aids you'll ever find. Both are available through O'Reilley Associates and can be found at any Barnes'n'Nobles or Borders, as well as through Amazon.com.

The second thing is that you don't need Perl to write an internet mail server. maild works just fine, on Unix. On Win32, there are a number of free (and not-so-free) applications that do just that.

Also, you can create mailing groups at Yahoo, which will accomplish much of the same thing, I think.

If you're thinking about creating an ISP, I would NOT write your own, even if you were completely conversant in the language. People with more experience and more time and more knowledge have spent years pefecting these kinds of things. Leverage their knowledge! :)

Oh - one more thing. If you expect to do a lot of Perl, I'd create an account here. After the books, this site is the most valuable Perl resource I've ever found, and I do this for a living. (Thanks, vroom!)

Update: jeffa suggested that you also look at Network Programming in Perl (ISBN:020161571). I've never read it, but, if you really want to write an internet mail server in Perl, it probably will turn out to be invaluable.

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/me wants to be the brightest bulb in the chandelier!

Vote paco for President!