Is it illegal for a registered sex offender to use a social networking site at all times?

What about those sex offenders only had their friends on their profile and weren't messaging every 12 year old they find online, are they still banned from the site?

Seems a bit crap to me but then again, I don't care too much. "Peederfiles" sure, ban them, shoot them and the like but as has been stated sex offender != peederfile.