For LDAP, there's a great tutorial on the IBM DeveloperWorks site here.<BR><BR>And as far as reasons to go with Linux for your mail server ...

“Linux terminal tutorial, aimed at those migrating from Windows, and users of single board computers including the Raspberry Pi. Covers a range of terminal commands and Linux concepts, including ...

The open source company is bundling e-mail and groupware applications with its Linux server operating system in a new product aimed at the business market.