Doublemochaman:
I believe you can lock the thread.
Nope.
As soon as someone replies to a reply, the thread has children (not my term).
I ran into this many months ago with a thread of mine that was destroyed by some members that will remain nameless.
I tried to lock it but because of the 'children' the thread kept spiraling down into a heap of ****.
See, just goes to show...... children will make your life more difficult...... :)
Happy hitting