Under attack

Within the last two days, we have a had a flood of users submitting forms through chronoforms. Our form requires a "captcha" and has email verification as well. They are coming from various IP addresses and I'm not sure what they are trying to accomplish, perhaps a security hack? Any feedback on what security breaches might be exposed would be appreciated. Here is an example of one --

Name: Andrea Lucianous
Store Name: BRAZIL Lucianous
Store Location: Rua Raul Marinho Briquet,140,Bl08 Ap04.
Jardim Esperanca
Mogi das Cruzes - SP
CEP 08743-585
BRAZIL
Email: [email]andr.eluandre.lu@gmail.com[/email]
Submitted by 177.35.160.246

Hi dbrody,

Sorry, I have no bright ideas. The Joomla! security forums / list may be more helpful. Normally the Captcha plus Email verification will keep out all but the most determined spammers.

Bob