Qpopper 4.0 is now available. Read up on the benefits of 3.0 and 3.1 before you move to 4.0. Qpopper supports the latest standards, and includes a large number of optional features. Qpopper is normally used with standard UNIX mail transfer and delivery agents such as sendmail or smail. The 3 and later code base has multiple levels of protection again common security vulnerabilities, so even if there is a bug at one level, the other levels can protect against an exploit.
Stability means running without crashing or other problems.
All bug reports are reviewed and taken seriously. Safety means protecting the user's mail. Qpopper takes extra precautions to guard against spool corruption, even if there is a system crash or power failure during an update. Qpopper provides a large number of features , such as bulletins, support for wireless devices, APOP, integration with packages such as Kerberos, drac, etc. Qpopper strives for the maximum possible performance consistent with safety.