Mozilla Mail & Newsgroups
Mozilla Mail & Newsgroups featured e.g. support for relevant protocols such as IMAP, POP3 and SMTP, a built-in Bayesian spam filter, support for multiple accounts, etc. The feature set was mostly comparable with that of the stand-alone alternative, Mozilla Thunderbird. This was because the two applications shared the same codebase for most things except the user interface.
Mozilla Application Suite has been superseded by SeaMonkey and the email and news client is now SeaMonkey Mail & Newsgroups. A re-packaged version of Mozilla Mail and Newsgroups was also included in Netscape versions 6 and 7, known as Netscape Mail & Newsgroups, and also appears in Classilla.