HD users who are playing without the v2.2 universal update can obtain lockboxes! I am on Version 2.1.3HD, Build 140, Data 20120208_08b.*
Unfortunately, there is no way to see how many you have or unlock them if you do have any.
You can lose them in PvP though, I have a post in my news feed telling me "During the fight, you lost 1 lockbox".
So this seems to greatly benefit all you lucky universal 2.2 users. If you have rivals who are known to be using CCHD, you will likely have a greater chance of obtaining a lockbox from them because they can't see them or open them!
So much for game balance. Mossbergs should have their stats reinstated over this.
*(Side note: Does anyone know if multi-click loot drop has been reset to "completion" for this data set? I haven't had loot drop from missions since the universal update, although I am getting invisible lockboxes.)
Edit: Nadya just gave me a gift on hit 3/5, so multi-click can still drop per click in this version.