I think adding things such as a confirmation page.., etc will help deter some spammers. But I guess if a spammer is determined enough and has some knowledge then they could be able to get through pretty much anything.

A better method would be to implement something like what Alex mentioned above, that Paypals use. You could integrate this into the add confirm. Shouldn't be that hard to do and if I get a few minutes of free time I'll take a quick look at it.

Glenn

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