There has been an ever increasing battle that ArtSites and all other web tools have been fighting with web spammers. We have several unique techniques that stop about 99% of spam messages from getting through our filters. Unfortunately, the spammers are getting more sophisticated so that requires our filtering techniques to get smarter too. We have been testing some new filters for a little while and have acquired data on thousands of spammers that we are now using to prevent them from using our Guestbook, Contact or Mailing List pages to send spam to our artists.
There is an incredibly small chance that some visitor's activities might trigger this spam warning as well. We have placed an email address and requested feedback in that warning to find out if any legitimate user is tripping over this but if you have any problems or hear of any of your visitors running into this, please let us know.