Bug 128468

Version:            (using KDE KDE 3.5.3)
Installed from:    00

* domain owners do have usally nearly unlimited aliases, and so we can include the password in the alias.
* two lists are needed for this:
1. whitelist with all allowed aliases
2. blacklist with all the spammed aliases
** an entry in the whitelist will be only possible if the alias is not in the blacklist (because it was spammed in the past)
** an entry in the blacklist is always possible but the alias should be removed from the whitelist
** the lists are header filters
** whitelisted aliases pass the filter; blacklisted aliases are rejected; not listed aliases are rejected or put in a special  directory "spam suspicion"
* so every contact gets its own (exclusivly known) email alias
** the local part of the alias should have at least 20 digits
** case spam arrives, there is security hole
** there can be an association with the contacts email adress which is also checked by the filter

eg: Mr. Foo gives me his adress foo@bar.com, so i create an email alias of my domain boo.com called xyz@boo.com and it gets whitelisted. Then Mr. Foo sends me a mail and the filter has to check if To: refers to xyz@boo.com and From: refers to foo@bar.com to get it pass.