For your information:
Since I use this captcha I did not have any spam. Before I used this captcha I had until 250 entrys per day in my guestbook but now no spam anymore. I could see several times spamers trying to enter new spam but this did not work.
Thank you to moazebulon.
Akkarin
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I am very happy to see this reply but I want to say that I'm not the only one to do this work.
In fact I do the less job by only creating a package to make this captcha work with easy-captcha.
The biggest work was made by rondomontano like I says in the xml file :
<description>This captcha generates an image with addition numbers which have to be entered. This Captcha requires the GD library with freetype-support. Captcha Author http://rodomontano.altervista.org/engcaptcha.php. esayCaptcha-Captcha Extension Author http://xavier.larquet.free.fr/xav2</description>
So also thanks to Rodomontano
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