[TYPO3] Spam protecting forms in TYPO3 ?

[Gunnar Jonsson]

This summer the problem with spam generators have become serious in general 
TYPO3 forms. I have looked into extension Captcha in order to protect 
ordinary forms in TYPO3 from spam. However, it seems to be necessary to 
adjust the source code in TYPO3 in ordre to spam protect forms in TYPO3. Is 
it someone who knows where in the sourcecode you have to insert the code for 
Captcha in ordre to spamprotect forms ? Or does it exist any extension which 
add Captcha functionality into ordinary TYPO3 forms ?

Best regards,
Gunnar Jonsson