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Hi Joomlers,
Does anybody have an idea for avoiding spam messages in Joomlaboard forum (in Joomla 1.0.13 installation)?

Sometimes in my Joomlaboard forum spam message surprised. (repeatedly with porn content).
I need to set to allow for all users (not only registered and logged) add message to forum (in Joomlaboard configuration -> Security -> Registered Users Only: No).
Forum is not moderated also.

I would need some idea (tool? plugin? add captcha?) for prohibit to enter these spam messages with images (although setting in Joomlaboard configuration -> Uploads -> Allow Public Upload for Images: No, Allow File Upload for Public: No)

thanks
Fred