Unfortunately forum spamming is extremely widespread. The newly formed
FiatClub500 got so much spam on their forum that they had to close it. They restarted later with tighter security but by then nobody wanted to use it and only has a handful of members now.
We too were infiltrated a while back but luckily Kevin was fast enough in removing the offending posts before too much harm was done.
Have a look at
http://www.stopforumspam.com/ to get an idea how bad the problem is.? I use that website to filter most new applications for membership.