LeonidS I tried deleting it from the database, but then people can't type in names to create new conversations and messages. How can I instead restrict @mentions to "friends only"? I think this will solve the problem with people sending random messages to other users and it will also solve the problem with unwanted profile names displaying in the popup list so sensitive or underage users don't get offended or harassed.

And then we also need to make the start conversation and message blocks on profiles to be shown to friends only. Any other ideas on how to make it a friends only network? Could we create a "who can contact me" privacy option?