The POP3 module tests accounts against the POP3 service.
The module has a single option, MODE. If left unset, the default behavior is to check for either "+" or "-" in the server's response to see if the attempt was successful.
If the server being tested in an AS/400, the module should be executed
using the option -m MODE:AS400. This will result in the -ERR
message being returned to be parsed for addition information. This is
based on information gathered from the following document:
Enumeration_of_AS400_users_via_pop3.pdf
Medusa Documentation