Several other Web-mail packages exist, often with more features but also with added complexity in installation. Here are some that have become well known. (A larger annotated list can be found at http://www.cru.fr/http-mail/ if you would like to check out other solutions.)
http://www.squirrelmail.org : It uses PHP4, IMAP, and HTML 4.0 without Javascript to be a rather feature-rich e-mail client. It's pretty lightweight, too, and can integrate into a large organization's e-mail directory using LDAP.
http://www. horde .org/imp/ : IMP is a powerful Web-mail system that is quite feature rich and very usable. It features great online help, a large language set that it can work with, and great scalability. Installation, however, can be a bit difficult for the uninitiated. Its biggest selling point is integration with a variety of mail server types. Because of its complexity, you may be tempted to install from precompiles and configured RPM packages.
http:// prometheus .zerodivide.net/apps/pimp/ : This is a project from a former IMP developer. It strives to be feature rich without expecting fancy work on the client end. No cookies are used, no Javascript or frames , and it can utilize a large database for preferences. MySQL is required, and LDAP is not supported at this time.
http://twig.screwdriver.net/ : TWIG isn't just simply a Web-mail client, it can also work as a groupware setup. It features calendaring, messaging, and Usenet support and great usability. It's also very easy to install.