As of Minecraft 1.8, hints are displayed upon hovering on the enchant slot:

Using ProtocolLib, it is possible to hide the tooltip: http://pastebin.com/L7XuVwVS
Notice: I used PacketWrapper library, but it is possible to make it without it.

It would be appreciated if we could choose if we want to hide the tooltips, as they display incorrect enchant because of the custom enchants that the client does not know about.