Spamming problem

[puneetps]

I'm trying to find a solution for stopping spams on my website http://www.hotbmarks.com.. I saw some option in the setting that a user can't post a second link of the same domain but couldn't find where are those settings. Moreover i found there are number of users registered for submitting link of a same website with some fishers management title..

[objective]

Its called Ego Squasher. Find it here