Sort:  

It is possible. However; it is difficult. The private message would have to be encrypted. They could also make the private message simply be a feature that does not interact with the blockchain.

Coin Marketplace

STEEM 0.20
TRX 0.25
JST 0.039
BTC 97530.27
ETH 3454.73
USDT 1.00
SBD 3.06