How about a .private and a .reply command.

[Thrawn]

They had this sort of thing in a mud I played in.  It would save bother of tuning a radio to someone on the roster and switching it back, in order to private someone.


Busher types:

          .private Thrawn Hi.


Thrawn recieives as a private message:

          Busher: Hi.


Thrawn types:

          .reply How are you doing?


Busher recieves as a private message:

          Thrawn: How are you doing?


Busher types:

          .reply Pretty good.


Thrawn recieves as a private message:

          Busher: Pretty good.

[Innominate]

You can do something similar by typing .radio x playername.

Good idea though, as this way it  wouldnt have to tie up a radio.