-----BEGIN BITCOIN SIGNED MESSAGE-----
March 7, 2015.
-----BEGIN SIGNATURE-----
HPX2xo5J+gHr17R9pOHOCexrfFb+N5beHlRftjD7BzTAFooZSzLxzeuDBwZT3uoZdc2xYcnT/Kxh993DLK5wvb0=
-----END BITCOIN SIGNED MESSAGE----
I told it is 'must'. The message should contain your username and a statement telling you are giving your account as collateral to Muhammed Zakir.
-MZ