function Lock_OnGossip(Unit, event, player)
        Unit:GossipCreateMenu(100, player, 0)
        Unit:GossipMenuAddItem( 0, "Test SetPlayerLock(true)", 1, 0)
        Unit:GossipMenuAddItem( 0, "Test SetPlayerLock(false)", 2, 0)
        Unit:GossipSendMenu(player)
end

function Lock_OnSelect(Unit, event, player, id, intid, code, pMisc)
    if (id == 0) then
        Unit:SendChatMessage(12, 0, "Locking", 0)
        player:SetPlayerLock(true)
        player:GossipComplete()
    end
    if (id == 1) then
        Unit:SendChatMessage(12, 0, "Unlocking", 0)
        player:SetPlayerLock(false)
        player:GossipComplete()
    end

end

RegisterUnitGossipEvent(1000, 1, Lock_OnGossip)
RegisterUnitGossipEvent(1000, 2, Lock_OnSelect)