This is simple stuff here. Firstly, it verifies ownership of the domain. I will never accept email from a host that does not resolve. Doing so will of course allow a ridiculous amount of spam from infected computers around the globe from regular IP addresses. The email address needs to match the host in which it is sending from as well. It requires hardly *any* work. Why are we even talking about this?
HELO, ELO, wants the hostname as well. Are we expecting millions of mail servers to simple change the way they're doing things? More importantly, if spam is a problem for you, I've had great luck with filtering services such as Postini and SpamSoap. Both excellent providers and have better resources than anything you can whip together on your little email server. It costs pennies as well.
I don't want to sound like one of those stoners preaching for legalization, but I truly believe the debate on the legalization of Marijuana is at the core of this whole fiasco. Here's why. We've already scientifically proven it doesn't have any long term negative health effects, besides when you burn it creating carbon monoxide which when inhaled could potentially give you lung cancer, yet there are things in this country much worse for you that are perfectly legal. Alcohol, fast food, etc. Not trying to say we should ban one thing or another, just let people decide what they want to do.
So the answer to the question, "why is this plant illegal to grow and consume?" is simply because of the huge industries that influence the rules, regulations, and laws in this country. Therefore, everything you and I are allowed or not allowed to do is most likely stemmed from some industry or conglomerate that has lobbied long enough and dumped enough capital in to the government to create the legislation. All I really want is for the Federal Government to just leave business alone. And the businesses need to leave the government alone. Businesses are not supposed to run our democracy. People are supposed to run our democracy. Small businesses have an incredibly difficult time staying afloat thanks to payroll taxes, unemployment insurance, sales tax, etc. They are the lower and middle class of the business world and they too are being treated like shit in this time of economic turmoil. I only bring up the Marijuana thing because it is a perfect example of how businesses influence the law and it has to stop. If you want certain laws to regulate what businesses can and cannot do, then it needs to be controlled on the State level, not the Federal level. Stop wasting our time and money.
To do nothing is to be nothing.