There are pathological people who are quite happy to spoil something good for everyone else if it is to their advantage. The internet in general is a great example of that and spam in particular.
On a good day, I receive about twice as many spam emails as legitimate emails. On a bad day it is worse.
Add to that there are constant attacks on the server and websites by people who are trying to hack a site so it will send spam, adding to the problem, and it is an ongoing pain in the arse.
In an effort to reduce the incoming spam count I have enabled one of the RBL’s (Realtime Black Lists).
The risk is always that it causes too many false positives – marking legit email as spam – and becoming a headache in itself.
If this works, it should be obvious within a day or so. Stand by for an update 😛