An Image captcha option is not a priority at this time.  The textual-question one works well and image-based captchas don't work well for folks who turn off images as well as accessibility problems for folks who access the website through browsers such as lynx.  For these reasons, I've shied away from implementing an image-based captcha solution.

Realize I'm describing random-value-on-the-fly image creation captcha. Vine Type would support a set of static images that you create -- instead of a question, you could put xhtml into the config file question.  Let me know if you'd like this explained further. 

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Sincerely,

Carl
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vine type - content management with standards in mind - vinetype.com
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