No offense, but wouldn't that be a good idea before replying?
It's not meant to be a user block list or an auto-block adder (though those should certainly be options you can enable, but disabled by default), it's about reading the content of IMs, usually only the first line, and accessing whether it's a message from a friend, or a load of rubbish/spam and auto close the IM and erase it from the chat log (enabled by default, or can be disabled for debug).
Clear enough?
Edit: Again.. shouldn't you read a post properly before adding your opinion?
The user's list would contain things like "VIAGRA", "V1@GRA" etc., and when the user receives another message like this, click the "This is a Spam IM" button on the IM window (or better in a list window) and it inserts the IM message words into the keyword filter, making sure not to add common ones like "is", "my" etc.
Here's an example:
<Name>, I cant upload my pics to msn for some reason!
But I want to chat with you.
you can find me on my personal page
http://CherylMayerstqv.blogspot.com
my name is kelly
So it should load that into a keyword filter, but exclude the names, and the url, since those can change. It won't be easy, it'll need to be an intelligent script, but it's possible, it's already done for email (Keyword Checking, Bayesian Analysis, SCL etc.).
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