The tools used to stop spam get in the way of stopping these messages precisely because they occupy that hard-to-define space between real junk and real messages.

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It will stop the spam that spoofs its origins because it only wants to collect live e-mail addresses, rather than sell goods.

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They are likely filtering for other offensive content as well, so they probably have means in place they could use to stop the spam.

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For instance, said Mr Hogan, filtering out e-mail messages that contain a web link can stop about 75% of spam.

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They tried to stop a couple of anti-spam software developers from using the term SPAM in their trademarks, but to no avail.

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"Even the SEC spam filter can't stop this, " Cox acknowledged in the press conference Thursday.

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Non-profit Spamhaus maintains what are known as "block lists" which many organisations use to spot sources of spam and other junk mail to stop them clogging mail servers and inboxes with unwanted messages.

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"It's worse than email spam, because it's hard to stop, " he says.

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With regards to spam, more responsibility should be taken by governments, ISP's and even the United nations to stop this pervasive and invasive nuisance.

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What we need to do to counter spam is not just to cut it off at a moving source, but to develop new ways to stop it.

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