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Add jcaptcha-all.jar (provided in bin-distribution) and ehcache.jar commons-collection-2.1 or greater (not provided see ehcache site commons collection ) to your application class path, ie in you WEB-INF/lib folder.

( since RC3, the default service implementation use a FastHashMap instead of ehcache Cache as CaptchaStore )

Instanciate a CaptchaService

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