GPG warning for integrity protection

[Meenal Pant]

Hello all,
When I decrypt a message I sometimes see this warning:

gpg: WARNING: message was not integrity protected

I read through the Open PGP RFC and understood that using MDC ensures
message integrity for encrypted messages. If I use MDC to encrypt
messages this warning will go away.

How can I use MDC for Public Key Encryption ? Does the key have an MDC
flag that needs to be set during key generation ?
Thanks
Meenal