The MODx vericode code sets the $_SESSION[’veriword’] variable when it generates the image.
Later, the user’s input is compared to that $_SESSION variable for validation.
reCaptcha isn’t setting the $_SESSION variable so you’d either need to set it yourself by getting the correct code from reCaptcha (if that’s possible), or find every instance where the $_SESSION variable check appears and replace it with a validation through the reCaptcha server.
BTW, many people find reCaptcha annoying because the images are so hard to read. I assume that you’re using it because bots can read the MODx vericode images (not sure how much of a problem that really is). Mollom is one alternative and there is a MODx Mollom class around here somewhere that should be relatively easy to integrate (though I don’t think anyone has done it yet).
The MODx SPForm snippet has the option of using a simple equation that the user has to solve as the image (e.g. 2 + 4 = ?). AFAIK, no bots have broken that. It uses a modified version of the MODx vericode.php file (included in the snippet .zip file) so it’s much easier to integrate with any standard MODx components.
Hope this helps.
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