Captcha in "ask me about this product" form

[studiowat]

Hello everybody,

I have the following problem:
We have problems wich spam. The spam is comming form the "ask me about this product form" There is no chaptcha. I need a captcha field there.
Oke i follow these steps:
- installed the plugin
- take a registration etc.
- put the registration etc in the plugin
- activate the plugin
Now i don't see a captcha field in my form.

Who can help me out.
thanks