Spammed Guestbook

Since March my guest book has been getting a lot of spam entries, but things came to a head during the past two weeks with up to 10 spam enties a day.

I have now dramatically changed the format of the guest book and have added a new “spambook” table in the mysql database.
I have also changed the form so that the guest book details are sent using the POST method instead of GET.
Any new posts that meet a few certain criteria are now put into the spambook table with the IP address and the user agent of the browser that is being used.

The new guest book has now been in operation for two-three day and has already collected 20 spam entries in the new table.
From these “entries” i have learnt that the spammers use a different IP address every time they post a new entry, even if they are within minutes of the last one. They are also using the same browser:

Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)

They have also set the country that they come from as “Other”, even though i don’t have an option for “Other”

Until the spammers realise that their “entries” are not being submited, my guest book should remain spam free for the time being