Has anyone written an Akismet-like, anti-SPAM extension for Yii?
I checked out this extension, but it won’t work since the developer states that it conflicts with Yii Active forms:
http://www.yiiframework.com/extension/aii-anti-spam-behavior/
TIA!
Em
That extension does not conflict with active form.
Samdarks suggestions for improvements does conflict.
So just use it. 
Oops! I didn’t read closely enough. My resolution for 2012: RFMP!
Question: would you consider this extension as robust as Akismet?
No, far from it.
Akismet is (AFAIK) a bayesian network based (artificial intelligence) piece of software which has to be taught.
You can read about it here:
http://en.wikipedia…_spam_filtering
Basically it needs to know the difference between ham and spam.
If it falsely flags something as spam, you can flag it as ham and allow it to send the information to the central Akismet service server so that it can be taught to be better at guessing what’s spam. 
Akismet uses Bayesian filtering, and then something else.
Maybe it’s possible to find something implemented in PHP, if you don’t want to (or can’t) use the Akismet service.
They do have - of course: since Wordpress is PHP-based and Akismet is by Wordpress - a PHP API for it.
You can try to make use of defensio. There’s a PHP implementation for it. Not sure if there’s a Yii extension yet.
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