Depends if HID keyboard even differentiate between them.
I would set up a USB keyboard and sniff the traffic (Couple of programs around to do this, some VM's do it too.) under 4 different scenarios. (Same sentence for example.)
1. Lowercase
2. Uppercase (holding down shift)
3. Caps lock on without shift
4. Caps lock on while holding shift.
Even if there are codes there that aren't in the libraries, it would be trivially easy to add them. (If not boring.)