Today, I finally registered with Twitter. I'll be looking into a way to connect that to my blogs so each time I blog, I get a tweat eliminating the need for me to actually tweat for real.

Okay, that's fine, but guess what... they want me to verify my email address and it does not work.

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That email address works. I know, I receive tons of spam every hour. But I have a Grey List attached. This refuses the email the first time it is sent. It will be accepted later (the 2nd attempt as long as it is sent 5 min. or more after the first attempt...)

This mechanism eliminates most of the spam. I turn it off one night a while back and got 500 emails that night. Obviously,  none of which I was interested in.

Twitter has a page about this problem: http://help.twitter.com/forums/31935/entries/38521

What's funny is that they don't seem to know (as they say) how to fix it. It looks like somehow they use Google Mail (GMail) but not really. Several IP addresses are incorrectly defined. http://discuss.joyent.com/viewtopic.php?id=25392

Now, to solve the problem of Twitter and Greylist, just add twitter.com to your /etc/greylist/whitelist_clients file. (That's the default location for Ubuntu and Debian systems.)