See here..
http://www.oxwall.org/forum/topic/47111
You can put the reason for suspension in the box when you suspend them, there is a small bug where you cant see the reason in admin, the team is working to get that fixed. Maybe in this next update. They store the reason in the database but forgot to add it to the form in admin.Can I put the suspension reason in oxwall 1.8.3?
See here..
http://www.oxwall.org/forum/topic/47111